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A clever way to estimate enormous numbers - Michael Mitchell

Video vocabulary

process

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US / prə'ses /

UK / ˈprɑsˌɛs, ˈproˌsɛs /

A2
  • noun
  • Dealing with official forms in the way required
  • Set of changes that occur slowly and naturally
  • verb
  • To organize and use data in a computer
  • To deal with official forms in the way required
  • To prepare by treating something in a certain way
  • To adopt a set of actions that produce a result
  • To convert by putting something through a machine

with

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US / wɪð /

UK / wɪð, wɪθ /

A1
  • preposition
  • As an employee of a certain company
  • Against something or someone
  • By using something as a means
  • Due to; because of
  • Including
  • Possessing as a feature
  • Related to
  • (Of the manner/attitude by which you do something)
  • Used to express that people or things are together

can

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US / kæn /

UK / kən,kæn /

A1
  • noun
  • A metal container for storing food
  • other
  • Able to; have the skill to; have the time to
  • verb
  • To have permission to
  • To be possible to do
  • To preserve food by sealing it in a metal container

manageable

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US / ˈmænɪdʒəbl /

UK / ˈmænɪdʒəbəl /

A2
  • adjecitve
  • Able to be managed or controlled

tnt

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US / ˌtiː en ˈtiː /

UK / ˌtiː en ˈtiː /

A1
  • noun
  • Explosive material

unsure

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US / ˌʌnˈʃʊə(r) /

UK / ʌnˈʃʊr, -ˈʃə:r /

B1
  • adjecitve
  • Lacking confidence or certainty
  • Lacking confidence in your own words or actions

ability

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US / ə'bɪlətɪ /

UK / əˈbɪlɪti /

A2
  • noun
  • The power, resources or skill to do something

but

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US / bət /

UK / bʌt,bət /

A1
  • conjunction
  • Used before you say something different, opposite

especially

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US / ɪˈspeʃəli /

UK / ɛˈspɛʃəli, ɪˈspɛʃ- /

A1
  • adverb
  • More than usual; extremely

give

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US / ɡɪv /

UK / ɡɪv /

A1
  • noun
  • Degree of flexibility in something, a material
  • verb
  • To hand over or present something to someone
  • To cause someone to have or experience something

book

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US / bʊk /

UK / bʊk /

A1
  • noun
  • Thing made of pages with writing on that you read
  • verb
  • (Police) to officially record someone's crimes
  • To reserve (hotel room, etc.) in advance
  • To produce a red or yellow card to a soccer player

seven

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US / ˈsevn /

UK / ˈsɛvən /

A1
  • number
  • Number 7

usually

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US / ˈju:ʒuəli /

UK / ˈjuːʒuəli /

A1
  • adverb
  • Normally; regularly

want

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US / wɔnt /

UK / wɑnt, wɔnt /

A1
  • noun
  • Something you desire or wish for
  • State or condition of poverty
  • verb
  • To desire or wish for something; hope for a thing

become

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US / bɪ'kʌm /

UK / bɪˈkʌm /

A1
  • verb
  • To begin to be; grow to be; develop into
  • To be suitable for a particular job or role

child

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US / tʃaɪld /

UK / tʃaɪld /

A1
  • noun
  • A very young person, between about 2 and 15

same

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US / seɪm /

UK / sem /

A1
  • adjecitve
  • Being equal in quality and amount
  • Identical; not different
  • Not changing; constant

tune

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US / tju:n /

UK / tun, tjun /

A2
  • noun
  • Group of musical notes that make a pleasant sound
  • verb
  • To make adjustments to equipment to make it better
  • To adjust to be at the right musical pitch
  • To modify how something operates, looks, e.g. car

not

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US / nɒt /

UK / nɑt /

A1
  • adverb
  • Word indicating the negative
  • (Used to form the negative of verbs)

reasonable

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US / ˈri:znəbl /

UK / ˈrizənəbəl /

A2
  • adjecitve
  • Being somewhat good, but not great
  • Fair and sensible; appropriate

our

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US / 'aʊə(r) /

UK / aʊr /

A1
  • determiner
  • Belonging to us

represent

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US / ˌreprɪ'zent /

UK / ˌrɛprɪˈzɛnt /

A2
  • verb
  • To depict art objects, figures, scenes; to portray
  • To show or describe something in a particular way
  • To act on behalf of others in government
  • To act or speak for another person or other people

whether

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US / ˈweðə(r) /

UK / ˈhwɛðɚ, ˈwɛð- /

A1
  • conjunction
  • If something will happen or not

overestimate

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US / ˌəʊvərˈestɪmeɪt /

UK / ˌoʊvərˈestɪmeɪt /

B2
  • verb
  • To make a guess higher than you should do

deal

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US / di:l /

UK / dil /

A1
  • verb
  • To cope with something - usually troubles
  • To give (something bad e.g. news) to
  • To buy and sell illegal drugs
  • To give out (cards, etc.) to; distribute
  • To do business with someone or to sell products

now

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US / naʊ /

UK / naʊ /

A1
  • adverb
  • At the present time or moment
  • Right away or in the next possible moment
  • Used to refer to something that just happened
  • Time between the present and a moment in the past
  • conjunction
  • Resulting from or because of something

accurate

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US / ˈækjərət /

UK / ˈækjərɪt /

A2
  • adjecitve
  • With no mistake or error; Correct

large

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US / lɑ:dʒ /

UK / lɑ:rdʒ /

A1
  • adjecitve
  • Big; of great size; broad, tall, wide, or fat

blast

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US / blɑ:st /

UK / blæst /

B1
  • noun
  • Destructive wave of air from an explosion
  • Strong current of wind
  • verb
  • To attack someone with words
  • To destroy something with explosives
  • To make a loud noise on or with something

enrico

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US / ɪn'rɪtʃ /

UK / ɛnˈrɪtʃ /

A1

latter

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US / 'lætə(r) /

UK / ˈlætɚ /

A2
  • adjecitve
  • Near the end off
  • adverb
  • Being the second of two people, things
  • noun
  • The second or last mentioned thing

name

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US / neɪm /

UK / nem /

A1
  • noun
  • What something or someone is called
  • verb
  • To state what someone is called, e.g. John

rather

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US / 'rɑ:ðə(r) /

UK / ˈræðɚ, ˈrɑðɚ /

A1
  • adverb
  • Somewhat; fairly; not that much

height

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US / haɪt /

UK / haɪt /

A2
  • noun
  • Distance of something from the bottom to the top

approximately

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US / əˈprɒksɪmətli /

UK / əˈprɑksəmɪtlɪ /

A2
  • adverb
  • Around; nearly; almost; about (a number)

estimation

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US / ˌestɪˈmeɪʃn /

UK / ˌɛstəˈmeʃən /

A2
  • noun
  • Judgment; opinion; guess at the value of

where

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US / hwɛə /

UK / hwɛr, wɛr /

A1
  • conjunction
  • At or in the place which
  • In whatever place
  • pronoun
  • Word you use to ask the location of something

tree

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US / tri: /

UK / tri /

A1
  • noun
  • Tall green plants in a forest

out

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US / aʊt /

UK / aʊt /

A1
  • adverb
  • No longer stylish (e.g. fashion)
  • Away from home, business, or the usual place
  • In a direction/movement away from inside or center
  • noun
  • Act when a batter cannot continue playing
  • verb
  • To tell people a secret

hey

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US / heɪ /

UK / he /

A1
  • exclamation
  • What you say when you want someone's attention

any

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US / 'enɪ /

UK / ˈɛni /

A1
  • adjecitve
  • One, or some, no matter which
  • pronoun
  • One (thing) of many; some

come

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US / kʌm /

UK / kʌm /

A1
  • verb
  • To arrive at a place
  • (Of mail) to be delivered
  • To move toward someone; go with someone
  • To reach a certain point or state

population

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US / ˌpɒpjuˈleɪʃn /

UK / ˌpɑpjəˈleʃən /

A2
  • noun
  • Number of people who live in a country, area etc.

tuner

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US / ˈtju:nə(r) /

UK / ˈtu:nə(r) /

B1
  • noun
  • Someone who modifies the operation or looks of
  • Someone who tunes pianos
  • An electronic receiver that detects radio signals

use

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US / ju:s /

UK / ju:s /

A1
  • noun
  • Ability to employ something
  • Need to enable it to work
  • Permission to do something with something
  • Act of spending money
  • Operation of a machine for its function
  • verb
  • To have; to eat, drink, consume etc.
  • To need to operate or work
  • To operate a machine, e.g. a computer
  • To treat a person badly
  • To do something with, for a task or purpose

write

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US / raɪt /

UK / raɪt /

A1
  • verb
  • To compose letters and words on paper or a screen
  • To invent or create a computer program
  • To create a song or piece of music

million

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US / ˈmɪljən /

UK / ˈmɪljən /

A1
  • number
  • 1,000,000

piano

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US / piˈænəʊ /

UK / piˈæno, ˈpjæno /

A2
  • adjecitve
  • In a soft and quiet manner (on the piano)
  • noun
  • Keyboard instrument used for playing music

while

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US / waɪl /

UK / hwaɪl, waɪl /

A1
  • conjunction
  • In spite of the fact that; although
  • During the time that; at the same time
  • noun
  • Short amount of time

after

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US / 'ɑ:ftə(r) /

UK / ˈæftɚ /

A1
  • adverb
  • Later than another time, or behind something
  • conjunction
  • Following something before
  • preposition
  • When an event happened or time has passed

appear

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US / ə'pɪə(r) /

UK / əˈpɪr /

A1
  • verb
  • To be seen, become visible; come into sight
  • To seem to be
  • To act in a play, movie, or be mentioned in media

guess

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US / ɡes /

UK / ɡɛs /

A1
  • noun
  • Answer given when you don't know if it is correct
  • verb
  • To give an answer without knowing if it is correct

many

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US / 'menɪ /

UK / ˈmɛni /

A1
  • determiner
  • Used to refer a large number of things

will

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US / wɪl /

UK / wɪl /

A1
  • noun
  • Desire or choice of someone
  • Document saying who gets your money when you die
  • Strong desire to do something; determination
  • Desire to do something; strong wish to do
  • other
  • Used with verbs to express the future
  • verb
  • To leave property to someone after your death
  • To use mental effort to make something happen
  • Am (is, are) likely to do
  • To influence someone to do something
  • To make something happen by strongly wanting it

balance

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US / ˈbæləns /

UK / ˈbæləns /

A2
  • noun
  • Instrument for weighing things
  • Being stable; having equal weight on both sides
  • Money remaining after paying costs
  • verb
  • To be steady by having equal weight on both sides
  • To make two or more things equal

continue

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US / kən'tɪnju: /

UK / kənˈtɪnju /

A1
  • verb
  • To do something without stopping, or after pausing
  • To start doing again after a break, pause, or stop

exactly

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US / ɪgˈzæktli /

UK / ɪɡˈzæktli /

A1
  • adverb
  • No more and no less than; precisely

handy

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US / 'hændɪ /

UK / ˈhændi /

B1
  • adjecitve
  • Convenient, easy to use, easy to reach
  • Being skillful in performing small tasks

science

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US / 'saɪəns /

UK / ˈsaɪəns /

A2
  • noun
  • Study of the physical world, based on facts

available

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US / əˈveɪləbl /

UK / əˈveləbəl /

A1
  • adjecitve
  • Present and able to be used
  • Able to be used at a scheduled time

either

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US / ˈaɪðə(r) /

UK / ˈiðɚ, ˈaɪðɚ /

A1
  • adjecitve
  • One of two (used when there is a choice of two)
  • adverb
  • (After negative statements) likewise, in addition
  • conjunction
  • Used as the first of two connected things
  • determiner
  • Used as the first of two connected things
  • pronoun
  • The one or the other

quick

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US / kwɪk /

UK / kwɪk /

A1
  • adjecitve
  • Using very little time; moving far in little time
  • Learning and understanding rapidly and easily

small

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US / smɔ:l /

UK / smɔl /

A1
  • adjecitve
  • Little in size; not big
  • (Of letters) not written in capital letters
  • Being insignificant or minor
  • (Of a business) with few people or things; local
  • (Of voice) being soft and quiet
  • (Of a child) being young

scientific

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US / ˌsaɪənˈtɪfɪk /

UK / ˌsaɪənˈtɪfɪk /

A2
  • adjecitve
  • Concerning academic study of the physical world

tool

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US / tu:l /

UK / tul /

A2
  • noun
  • Device used to make things, e.g. a hammer
  • verb
  • To provide a workshop with the right equipment

try

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US / traɪ /

UK / traɪ /

A1
  • noun
  • Act of putting the ball over the rugby goal line
  • verb
  • To make an effort, to attempt to do something
  • To examine someone or something in a court of law
  • To test to see if it is good or you like it
  • To make a person go through hardship; test
  • To examine something to see if it works

previous

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US / ˈpri:viəs /

UK / ˈpriviəs /

A2
  • adjecitve
  • Existing or happening before the present time

uncertainty

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US / ʌn'sɜ:tntɪ /

UK / ʌnˈsə:tn:ti /

B2
  • noun
  • Feeling of not really knowing what will happen

day

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US / deɪ /

UK / de /

A1
  • noun
  • A period of 24 hours beginning at midnight
  • The period of time when it is light outside
  • Person's name

develop

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US / dɪ'veləp /

UK / dɪˈvɛləp /

A1
  • verb
  • To explain something in steps and in detail
  • To create or think of something
  • To grow bigger, more complex, or more advanced
  • To make a photograph from film

point

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US / pɔɪnt /

UK / pɔɪnt /

A1
  • noun
  • An item to be discussed
  • Small spot or dot
  • Fact or detail
  • Feature of something
  • The size of the text on a page or screen
  • A certain time or stage in a process
  • Certain position in time or space
  • Idea or fact you try to convince people about
  • Measurement of scores in a game, sport
  • Sharp end of something, e.g. a pen or pin
  • verb
  • To face a certain direction, e.g. north
  • To indicate something with your finger to others

skill

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US / skɪl /

UK / skɪl /

A2
  • noun
  • Ability to do something well

could

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US / kəd /

UK / kʊd /

A1
  • other
  • Past form of 'can' to mean have ability
  • Used to ask for something politely, or to offer

know

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US / nəʊ /

UK / noʊ /

A1
  • verb
  • To be familiar with a person or place, thing
  • To feel sure or be convinced about something
  • To discover or be aware of something
  • To be able to distinguish
  • To have knowledge of things

often

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US / ˈɔfən /

UK / ˈɔfən,ˈɑfən,ˈɔftən,ˈɑf- /

A1
  • adverb
  • Many times; frequently; on many occasions

estimate

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US / 'estɪmət /

UK / ˈɛstəˌmet /

A2
  • noun
  • Guess or calculation of cost, size or value
  • verb
  • To guess or calculate the cost, size or value of

meter

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US / ˈmi:tə(r) /

UK / ˈmitɚ /

A1
  • noun
  • Unit of length equal to 100 cm or about 39 inches
  • Device for measuring things e.g. gas
  • Device to put money into to rent a parking place
  • Rhythm of a poem
  • verb
  • To measure water, etc. when it has to be paid for

hundred

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US / 'hʌndrəd /

UK / ˈhʌndrɪd /

A1
  • number
  • 100

chicago

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US / ʃɪ'kɑ:gəʊ, -'kɔ:- /

UK / ʃɪ'kɑ:ɡoʊˌ -'kɔ:- /

A1
  • proper noun
  • A city in northeastern Illinois, on Lake Michigan; population 2,853,114 (est. 2008). Chicago develop

fall

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US / fɔ:l /

UK / fɔl /

A1
  • noun
  • Season after summer and before winter; Autumn
  • A drop in amount; decrease
  • Dropping from a standing position to the ground
  • verb
  • To drop in amount; to decrease
  • To come down from a higher position suddenly
  • To go from standing to the ground, by accident

diameter

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US / daɪˈæmɪtə(r) /

UK / daɪˈæmɪtɚ /

B1
  • noun
  • Distance across the center of an object

negative

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US / 'neɡətɪv /

UK / ˈnɛɡətɪv /

A2
  • adjecitve
  • Being harmful, unwanted or unhelpful
  • In mathematics, being less than zero
  • Focusing on the bad aspects; pessimistic
  • noun
  • The opposite to a positive electrical charge
  • In grammar, containing words such as 'no' or 'not'
  • Reply to a question or statement that means 'no'
  • Image on camera film used to make a photo

serve

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US / sɜ:v /

UK / sɚv /

A2
  • verb
  • To act in a particular position or office
  • To hit the first ball to an opponent in tennis etc.
  • To be used for a particular purpose
  • To give someone food or drinks
  • To give a person or group a service that is needed
  • To spend a particular amount of time in prison
  • To help customers find products and making sales
  • To give an official paper to appear in court

problem

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US / ˈprɒbləm /

UK / ˈprɑbləm /

A1
  • adjecitve
  • Causing trouble
  • noun
  • Something difficult to deal with or causes trouble
  • Question to show understanding of a math concept

six

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US / sɪks /

UK / sɪks /

A1
  • number
  • 6

datum

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US / ˈdeɪtəm /

UK / ˈdetəm, ˈdætəm, ˈdɑtəm /

B1
  • noun
  • Item of factual information

distance

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US / 'dɪstəns /

UK / ˈdɪstəns /

A2
  • noun
  • Lack of friendliness toward another person
  • Amount of space between two places or things
  • verb
  • To make it clear that you are not involved

jar

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US / dʒɑ:(r) /

UK / dʒɑr /

B2
  • noun
  • Glass container for foods
  • verb
  • To have a harsh or unsettling effect on someone
  • To make a harsh sound to the ears

think

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US / θɪŋk /

UK / θɪŋk /

A1
  • verb
  • To have an idea about something without certainty
  • To have an idea, opinion or belief about something

and

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US / ənd /

UK / ənd, ən,ænd /

A1
  • conjunction
  • Used to refer to two or more things
  • Plus; in addition; on top of that
  • Used to introduce an action that follows another

manhattan

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US / mæn'hætn /

UK / mæn'hætn: /

A1
  • noun
  • A cocktail made with whiskey and sweet vermouth with a dash of bitters
  • other
  • One of the five boroughs of New York City

format

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US / ˈfɔ:mæt /

UK / ˈfɔ:rmæt /

B1
  • noun
  • Form, design, or arrangement of something
  • verb
  • To set the appearance of a text in a certain way
  • To set a computer back to its original state

simple

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US / 'sɪmpl /

UK / ˈsɪmpəl /

A1
  • adjecitve
  • Not hard to understand or do; not complex
  • Having only a few parts; not complex
  • Being ordinary or normal
  • Being plain; without a lot added for style

travel

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US / ˈtrævl /

UK / ˈtrævəl /

A1
  • noun
  • Going to other places, esp. distant places
  • verb
  • To go to a place that is far away

look

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US / lʊk /

UK / lʊk /

A1
  • noun
  • Person's beauty or physical attractiveness
  • Particular style of dress, clothes, or appearance
  • The way someone, something appears to be
  • Act of searching for or examining something
  • verb
  • To appear to be; seem

multiply

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US / ˈmʌltɪplaɪ /

UK / ˈmʌltəˌplaɪ /

B1
  • verb
  • To increase in number by reproducing/having babies
  • To increase something by a large quantity
  • To have increased by a large quantity
  • To calculate two numbers e.g. 2 x 4

unsolvable

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US / 'ʌn'sɒlvəbl /

UK / 'ʌn'sɒlvəbl /

B1
  • adjecitve
  • (Of problem, etc.) not able to be solved/worked out

project

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US / prəˈdʒekt /

UK / prəˈdʒɛkt /

A1
  • noun
  • A planned piece of work for specific purpose
  • Group of homes built by government for poor people
  • verb
  • To predict what will happen in the future
  • To show something on a screen using light
  • To stick out past the edge of something

list

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US / lɪst /

UK / lɪst /

A1
  • noun
  • Lean of a boat to one side
  • Series of written names, words or numbers
  • verb
  • To lean to one side, like a boat or ship
  • To present for sale for a specific price
  • To write a series of names, words, or numbers

pretty

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US / 'prɪtɪ /

UK / ˈprɪti /

A1
  • adjecitve
  • Being attractive to the eye in a simple way
  • adverb
  • Very; to a great degree

rapid

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US / ˈræpɪd /

UK / ˈræpɪd /

B1
  • adjecitve
  • Moving or happening very quickly
  • noun
  • Rough and fast-moving part of a river

speed

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US / spi:d /

UK / spid /

A2
  • noun
  • How fast or slow something is or is done
  • verb
  • To move quickly when completing an action
  • To drive a vehicle faster than laws allow

paper

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US / ˈpeɪpə(r) /

UK / ˈpeɪpər /

A1
  • adjecitve
  • Not existing in reality, or done infrequently
  • Made from the material that we use to make books
  • noun
  • Academic writing or a talk on a specific topic
  • Written test
  • Newspaper
  • Pages of a book are made from this

atom

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US / 'ætəm /

UK / ˈætəm /

B1
  • noun
  • Smallest bit that matter can be broken down into

kiloton

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US / 'kɪlətʌn /

UK / 'kɪləˌtʌn /

A1
  • noun
  • One thousand ton

they

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US / ðeɪ /

UK / ðe /

A1
  • pronoun
  • Two or more people, animals, or things

fourth

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US / fɔ:θ /

UK / fɔ:rθ /

A1
  • noun
  • 4th

work

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US / wɜ:k /

UK / wɚk /

A1
  • adjecitve
  • Activity completed in order to make money
  • noun
  • The product of some artistic or literary endeavor
  • Everything created by an author, artist, musician
  • Activity you do in order to make money
  • Place of employment
  • Final product or result of a some labor or effort
  • verb
  • To bring into a specific state of success
  • To be functioning properly, e.g. a car
  • To do your job in your company or workplace
  • To make an effort to do something
  • To operate a machine or device

all

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US / ɔ:l /

UK / ɔl /

A1
  • adverb
  • Completely; totally
  • determiner
  • Being every one of something
  • pronoun
  • 100% of something; the complete amount

drop

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US / drɒp /

UK / drɑp /

A1
  • noun
  • Distance between a higher and a lower level
  • Act of letting something fall (from your hand)
  • A decrease in quantity or quality; reduction
  • Tiny amount of liquid, with rounded bottom
  • verb
  • To drive someone to a place and then drive away
  • To let something fall from your hand
  • To fall or lie down quickly, as when shot
  • To decide to stop something e.g. a course)
  • To (cause to) reduce in quantity or quality

produce

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US / prə'dju:s /

UK / prəˈdus, -ˈdjus, pro- /

A1
  • noun
  • Fresh foods such as fruits and vegetables
  • verb
  • To grow something naturally
  • To make something appear
  • To manufacture something using machines
  • To control the making a movie or television show

who

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US / hu: /

UK / hu /

A1
  • pronoun
  • Which person
  • Used to introduce information about people

famous

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US / 'feɪməs /

UK / ˈfeməs /

A1
  • adjecitve
  • Excellent
  • Widely known; recognized by many people

perfect

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US / 'pɜ:fɪkt /

UK / ˈpɚfɪkt /

A1
  • adjecitve
  • So good it cannot be improved
  • verb
  • To do something so well, it cannot be done better

phone

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US / fəʊn /

UK / foʊn /

A2
  • noun
  • Machine used to talk to someone who is far away
  • verb
  • To talk to someone using a telephone

one

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US / wʌn /

UK / wʌn /

A1
  • pronoun
  • You; we; people in general; someone
  • The thing or person previously referred to
  • adjecitve
  • Used to refer to people generally
  • Being a strong example of (something mentioned)
  • number
  • Number 1

power

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US / 'paʊə(r) /

UK / ˈpaʊɚ /

A1
  • noun
  • Legal or official right to perform certain actions
  • Ability to move forcefully and quickly
  • Energy of something (e.g. electricity or fuel)
  • Mathematical way to multiply a number
  • Condition of being in political control
  • Physical force, energy, and strength
  • verb
  • To give energy to something, e.g. by electricity
  • To move something forcefully and quickly

strength

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US / streŋθ /

UK / strɛŋkθ, strɛŋθ, strɛnθ /

A2
  • noun
  • Condition of being strong

than

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US / ðən /

UK / ðən /

A1
  • conjunction
  • Used to compare two things that are not equal

other

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US / 'ʌðə(r) /

UK / ˈʌðər /

A1
  • adjecitve
  • A thing different from that mentioned
  • determiner
  • (Something) else; not the first (one)
  • pronoun
  • Being the one and only thing of that category

term

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US / tɜ:m /

UK / tɚm /

A1
  • noun
  • Conditions applying to an agreement, contract
  • Length of time something is expected to happen
  • Fixed period of weeks for learning at school
  • The (precise) name given to something
  • verb
  • To call; give a name to

three

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US / θri: /

UK / θri /

A1
  • number
  • Number 3

magnitude

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US / ˈmægnɪtju:d /

UK / ˈmæɡnɪˌtud, -ˌtjud /

B2
  • noun
  • Number representing force of an earthquake
  • Size or importance
  • Number representing the brightness of a star

make

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US / meɪk /

UK / mek /

A1
  • noun
  • Product made by a particular company; brand
  • verb
  • To arrange or prepare something e.g. dinner
  • To get to (a place) on time
  • To gain the status of (teacher, lawyer, etc.)
  • To create something by putting things together
  • To earn a certain amount of money at a job
  • To cause or force a person to do something
  • To cause something to happen or be formed

order

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US / 'ɔ:də(r) /

UK / ˈɔrdɚ /

A1
  • noun
  • Religious or social group, as of nuns
  • Instructions to others to do what you want
  • State in which things are neat and organized
  • What you ask to buy, e.g. food in restaurant
  • Social or political control of an area
  • verb
  • To put things in a sequence, e.g. a, b, c
  • To give instructions to others to do what you want
  • To ask for something you want to buy, e.g. a meal

essential

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US / ɪ'senʃl /

UK / ɪˈsɛnʃəl /

A2
  • adjecitve
  • Extremely or most important and necessary

underestimate

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US / ˌʌndər'estɪmeɪt /

UK / ˌʌndɚˈɛstəmet /

B2
  • verb
  • To make too low a guess of something's size, value

answer

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US / 'ɑ:nsə(r) /

UK / ˈænsɚ /

A1
  • noun
  • Reply to a question someone asks
  • Solution to a problem or test question
  • verb
  • To reply to a question someone asks
  • To solve a test question or a problem

illinois

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US / ˌɪlɪ'nɔɪ(z) /

UK / ˌɪlə'nɔɪ /

A1
  • other
  • A member of the Algonquian people formerly of Illinois and regions to the west
  • A midwestern state in north-central United States
  • Algonquian language of the Illinois and Miami

less

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US / les /

UK / lɛs /

A1
  • adjecitve
  • Smaller in amount or degree
  • adverb
  • To a smaller degree
  • noun
  • A smaller amount
  • preposition
  • With the subtraction of

trinity

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US / ˈtrɪnəti /

UK / 'trɪnətɪ /

B2
  • noun
  • Christianity union of Father, Son, and Holy Spirit

cumbersome

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US / ˈkʌmbəsəm /

UK / ˈkʌmbəsəm /

C1
  • adjecitve
  • Being slow, heavy or difficult to move

this

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US / ðɪs /

UK / ðɪs /

A1
  • adjecitve
  • Used to indicate something already been discussed
  • Used to indicate something happening around now
  • adverb
  • An indication by a physical motion or gesture
  • A specific amount of
  • determiner
  • Person, thing, or idea near you
  • pronoun
  • Person, thing that has already been discussed

may

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US / meɪ /

UK / me /

A1
  • noun
  • 5th month of the year
  • other
  • Used to express a desire
  • Expresses permission, possibility or probability
  • Used to show that a thing could be true

easily

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US / ˈi:zəli /

UK / ˈizəli /

A1
  • adverb
  • Clearly; without doubt; certainly
  • Without difficulty

little

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US / 'lɪtl /

UK / ˈlɪtl /

A1
  • adjecitve
  • Being short in length of time
  • Not great in size, amount, or degree; small
  • Being very young or younger than others
  • adverb
  • By an amount or degree that is not very much
  • Not often; rarely
  • noun
  • A person's name

the

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US / ðə /

UK / ðə /

A1
  • article
  • Used to refer to something already mentioned
  • Used to show there is only one of something
  • determiner
  • Used to describe all of a family

also

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US / 'ɔ:lsəʊ /

UK / ˈɔlso /

A1
  • adverb
  • In addition; too; in a similar way

live

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US / lɪv /

UK / liv /

A1
  • adjecitve
  • Being broadcast as events happen, not recorded
  • Carrying electric current; able to give a shock
  • Glowing because burning; hot
  • Not yet killed (for food)
  • adverb
  • (Music, drama) as it is performed
  • verb
  • To be alive
  • To experience a particular type of life
  • To make your home in a house or town

how

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US / haʊ /

UK / haʊ /

A1
  • adjecitve
  • To what degree? in what amount?
  • adverb
  • (Used to explain the way to do something)
  • exclamation
  • For what purpose or reason?
  • (Used to ask someone or something's condition)

five

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US / faɪv /

UK / faɪv /

A1
  • number
  • 5

sixth

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US / sɪksθ /

UK / sɪksθ /

A1
  • noun
  • 6th

year

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US / jə: /

UK / jɪr /

A1
  • noun
  • Unit of time equal to 12 months or 365 or 366 days
  • Used to refer to the age of a person

you

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US / jʊ /

UK / ju /

A1
  • pronoun
  • Person someone is speaking or writing to
  • Person or people in general

just

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US / dʒʌst /

UK / dʒʌst /

A1
  • adjecitve
  • Proper or appropriate; as is deserved
  • Doing or being what is right or fair
  • Legally correct; having enough evidence
  • adverb
  • Almost; nearly
  • Exactly at the time of
  • Exactly (the same as, like)

range

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US / reɪndʒ /

UK / rendʒ /

A2
  • noun
  • Cooking stove with multiple burners
  • Given distance from a point; how far plane can fly
  • Large grassy area where cattle wander and feed
  • Group or chain of mountains
  • Set of things with something in common
  • Limits within which something extends or varies
  • A set of products, e.g. so that people can choose
  • verb
  • To cover an area from one point to another
  • To extend to or vary within given limits
  • To put things in a row or in line
  • To wander or explore

atomic

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US / əˈtɒmɪk /

UK / əˈtɑ:mɪk /

B1
  • adjecitve
  • Concerning atoms

determine

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US / dɪ'tɜ:mɪn /

UK / dɪˈtɚmɪn /

A2
  • verb
  • To control exactly how something will be or act
  • To establish the facts about; discover

light

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US / laɪt /

UK / laɪt /

A1
  • adjecitve
  • Being bright making it easy to see; not dark
  • Being pale and lacking darkness of color
  • Not heavy; weighing only a little
  • adverb
  • Carrying few bags when traveling
  • noun
  • A source of energy that makes a room or area bright
  • Way in which something or someone is understood
  • verb
  • To cause something to burn; put a burning match to
  • To provide a way to see ahead

math

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US / mæθ /

UK / mæθ /

A2
  • noun
  • Study or science of numbers and shapes

correct

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US / kə'rekt /

UK / kəˈrɛkt /

A2
  • adjecitve
  • Being suitable and appropriate for an occasion
  • True or accurate
  • verb
  • To fix a problem
  • To write marks on a piece of work to show mistakes
  • To punish in order to improve

for

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US / fə(r) /

UK / fɔr,fə /

A1
  • preposition
  • Used to show the purpose, or need of something

time

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US / taɪm /

UK / taɪm /

A1
  • noun
  • Speed at which music is played; tempo
  • Point as shown on a clock, e.g. 3 p.m
  • Number of hours, minutes needed to do something
  • Occasion when something happens
  • Period or occasion that something occurred
  • Period in history or the past
  • Something measured in minutes, hours, days, etc.
  • How long an event takes; duration
  • verb
  • To check speed at which music is performed
  • To choose a specific moment to do something
  • To measure how long an event takes, e.g. a race
  • To schedule something to occur at a specific moment

through

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US / θru: /

UK / θru /

A2
  • adjecitve
  • having finished using or doing something
  • adverb
  • From the beginning of something until the end
  • preposition
  • Over, in, across an entire thing or place
  • Allowing you to pass between, or to
  • By a particular way or process; by the use of

exact

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US / ɪɡ'zækt /

UK / ɪɡˈzækt /

A2
  • adjecitve
  • Completely correct; accurate; specific
  • verb
  • To get something, sometimes using force

express

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US / ɪk'spres /

UK / ɪkˈsprɛs /

A1
  • adjecitve
  • Sent by a fast mail service
  • Traveling at high speed
  • noun
  • Fast train or bus
  • verb
  • To send something by fast mail
  • To state or show what you think or how you feel

piece

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US / pi:s /

UK / pis /

A1
  • noun
  • A counter in a board game
  • Small part of something larger
  • verb
  • To put items together to assemble something

start

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US / stɑ:t /

UK / stɑrt /

A1
  • noun
  • First time or place that a thing exists; beginning
  • First opportunity to achieve something, e.g. a job
  • Sudden action or movement because you are scared
  • other
  • Beginning of something in place or time
  • verb
  • To do, be or happen for the first time; begin
  • To turn something on

test

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US / test /

UK / test /

A1
  • noun
  • A medical examination
  • Action to establish the truth or nature of
  • Examination; questions to measure knowledge
  • verb
  • To be given a medical examination
  • To try to establish the truth or nature of
  • To ask a series of questions to measure knowledge

within

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US / wɪˈðɪn /

UK / wɪðˈɪn, wɪθ- /

A1
  • adverb
  • Inside the limits of an area, time or range
  • preposition
  • From the inside of something

well

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US / wel /

UK / wɛl /

A1
  • adjecitve
  • Being in a fortunate, good condition or state
  • Healthy and in good condition
  • adverb
  • In an acceptable, proper, or successful manner
  • In a complete, total, or full manner
  • A great and considerable degree
  • In a successful way, in a good or satisfactory way
  • exclamation
  • Used to begin or continue a particular statement
  • Used to show you want to start saying something
  • Used to express that you are waiting for a reply
  • You say this to change the topic of a conversation
  • Used to indicate you are making a final remark
  • noun
  • Long deep hole in the ground to get water
  • verb
  • To cause your eyes to fill with tears

begin

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US / bɪ'ɡɪn /

UK / ˈbeɡɪn /

A1
  • verb
  • To do the first part of an action; to start

eighth

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US / eɪtθ /

UK / etθ, eθ /

A1
  • noun
  • 8th

incredible

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US / ɪnˈkredəbl /

UK / ɪnˈkrɛdəbəl /

A2
  • adjecitve
  • Very good; amazing
  • Really good; amazing; great
  • Very hard to believe

per

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US / pə(r) /

UK / pɚ /

A2
  • preposition
  • In the manner directed or suggested
  • For each; during each

sound

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US / saʊnd /

UK / saʊnd /

A1
  • adjecitve
  • Sensible, dependable and reliable
  • Unbroken or undisturbed, as of sleep
  • Firm or solid in structure
  • Sane; not mentally ill
  • Clearly reasoned; involving sense, good judgment
  • noun
  • Unique quality that characterizes a style of music
  • Waves traveling in air or water that can be heard
  • verb
  • To seem or appear to be, from what was said
  • To say in a clear deliberate manner
  • To make a noise, e.g. to ring a bell

such

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US / sʌtʃ /

UK / sʌtʃ /

A1
  • determiner
  • Being similar to
  • (Thing) as previously stated or referred to
  • adverb
  • (Used to emphasize the quality of an adjective)

earth

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US / ɜ:θ /

UK / ɚθ /

A1
  • noun
  • Wire connecting an electrical device to the ground
  • The planet we live on
  • Soil in which we grow plants

few

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US / fju: /

UK / fju /

A1
  • pronoun
  • Not many, a small number

much

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US / mʌtʃ /

UK / mʌtʃ /

A1
  • adjecitve
  • Very; to a high level or degree
  • adverb
  • A lot; large amount; a high degree of
  • Nearly; basically
  • On many occasions; often
  • noun
  • A large amount; a great quantity

under

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US / ˈʌndə(r) /

UK / ˈʌndɚ /

A1
  • adjecitve
  • In the same place as another thing, but lower
  • adverb
  • In a lower quantity or price than expected
  • preposition
  • According to the terms of an agreement or law
  • Managed or controlled by the authority of
  • Being of a lesser quality or amount than expected
  • Influenced or affected by something or someone
  • Less or lower in age, amount, size or number

value

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US / 'vælju: /

UK / ˈvælju /

A1
  • noun
  • Importance you attach to something
  • Some information expressed as a number
  • Stated price of something; worth
  • verb
  • To place a high importance on something
  • To say how much money something is worth

case

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US / keɪs /

UK / kes /

A1
  • noun
  • Container used to carry things, e.g. clothes
  • Set of facts about a crime
  • Set of facts about an event
  • Example or instance of something
  • verb
  • To find out about a place, as in planning to steal

great

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US / ɡreɪt /

UK / ɡret /

A1
  • adjecitve
  • Very large in size
  • Very important
  • Very good; fantastic; wonderful
  • adverb
  • Very good; better than before
  • noun
  • Successful and well-admired person

find

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US / faɪnd /

UK / faɪnd /

A1
  • noun
  • Object discovered by chance
  • Things that have been discovered from searching
  • verb
  • To become aware of something that is happening
  • To discover or meet by chance
  • To decide if someone is guilty of a crime, or not
  • To learn through study, research, or effort
  • To discover something by looking for it

require

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US / rɪ'kwaɪə(r) /

UK / rɪˈkwaɪr /

A2
  • verb
  • To demand that someone does something
  • To need to do something, to make it necessary

bomb

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US / bɒm /

UK / bɑm /

B1
  • noun
  • An explosive device
  • verb
  • To attack with explosives
  • To fail or be completely unsuccessful

city

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US / 'sɪtɪ /

UK / ˈsɪti /

A1
  • noun
  • Area with many buildings, roads and people

example

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US / ɪgˈzɑ:mpl /

UK / ɪɡˈzæmpəl /

A1
  • noun
  • Thing, person which represents a category

each

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US / i:tʃ /

UK / itʃ /

A1
  • determiner
  • Every one of two or more things
  • pronoun
  • Per one person or thing

number

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US / ˈnʌmbə(r) /

UK / ˈnʌmbɚ /

A1
  • noun
  • Symbols such as 1, 2, 56, 793
  • Particular song or dance performed during a show
  • Total quantity or amount of things
  • verb
  • To put numbers on things
  • To assign a sequence within a group, series, set
  • To claim to be part of a larger group, series, set

tell

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US / tel /

UK / tɛl /

A1
  • verb
  • To (strongly) advise a person to do something
  • To be able to guess
  • To say or communicate information to someone
  • To inform, but without speaking; indicate
  • To have a negative effect on someone
  • To order someone to do something; command
  • To recognize something based on certain signs
  • To report something to an authority
  • To explain something or teach someone something

about

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US / ə'baʊt /

UK / əˈbaʊt /

A1
  • adverb
  • To be ready to; going to
  • Nearly; approximately; roughly
  • Near; next to; close to
  • In every direction; in the area of
  • preposition
  • Concerning or of (a topic)

again

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US / ə'ɡen /

UK / əˈɡɛn /

A1
  • adverb
  • One more time, once more

care

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US / keə(r) /

UK / kɛr /

A1
  • noun
  • Treatment you receive for your health or safety
  • Something that a person worries about
  • verb
  • To feel interest, concern, or worry
  • To look after someone or something

like

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US / laɪk /

UK / laɪk /

A1
  • adjecitve
  • Being equal in status or kind to something else
  • Similar; the same
  • adverb
  • For example
  • preposition
  • Used as a filler; used to ad emphasis
  • In a way similar to the way something is done
  • Such as; for example
  • verb
  • To want to
  • To find something pleasing; to prefer something

people

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US / 'pi:pl /

UK / ˈpipəl /

A1
  • noun
  • Persons sharing culture, country, background, etc.
  • Men, Women, Children

site

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US / saɪt /

UK / saɪt /

A2
  • noun
  • Place that is reserved for a particular activity
  • Location of building work
  • Location of something
  • Place where something of special interest happened
  • Website
  • verb
  • To place something in a particular position, area

second

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US / 'sekənd /

UK / ˈsɛkənd /

A1
  • adjecitve
  • 2nd; the one following first
  • noun
  • Unit of time; one sixtieth of a minute
  • Short period of time that you wait for someone
  • (Do) soon

that

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US / ðæt /

UK / ðæt, ðət /

A1
  • adjecitve
  • The person or thing being talked about
  • Used to identify something both the speakers know
  • adverb
  • Used to reinforce adjectives and adverbs
  • To such a degree
  • conjunction
  • Used to connect a noun clause
  • Used to introduce an adverbial clause
  • Used to introduce a noun clause
  • determiner
  • Used as a noun to refer to something
  • pronoun
  • Referring an object far away
  • Used to refer to the relative pronoun ‘which’

what

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US / wɒt /

UK / hwɑt, hwʌt, wɔt, wʌt,hwət, wət /

A1
  • pronoun
  • Thing or things that; the same kind as
  • Used to emphasize something you are about to say
  • adjecitve
  • Used to refer to a particular amount, or number
  • Used to place emphasis on a particular quality
  • adverb
  • To a certain degree
  • determiner
  • Question words used for asking for information
  • exclamation
  • Used to express excitement, shock, or surprise
  • Used to ask people to repeat something they said

during

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US / ˈdjʊərɪŋ /

UK / ˈdʊrɪŋ, ˈdjʊr- /

A1
  • preposition
  • At some point in the course of an event or thing

include

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US / ɪnˈklu:d /

UK / ɪnˈklud /

A1
  • verb
  • To make someone, something part of a group

must

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US / məst /

UK / mʌst /

A1
  • noun
  • Something that is necessary or required
  • other
  • (Used to state that something ought to be true)
  • Used to say something is required or necessary

physicist

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US / ˈfɪzɪsɪst /

UK / ˈfɪzɪsɪst /

B2
  • noun
  • Person who studies and works in physics

get

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US / ɡet /

UK / ɡɛt /

A1
  • verb
  • To become affected by illness or disease
  • To begin to feel or understand an emotion or idea
  • To send or bring someone or something home, etc.
  • To go somewhere to obtain something
  • To (cause to) do a particular thing
  • To obtain, receive or be given something
  • To currently have
  • To prepare for use
  • To understand something being said or read

first

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US / fɜ:st /

UK / fɚst /

A1
  • adjecitve
  • 1st; Coming before all others in time or place
  • noun
  • Something that has not happened before
  • Position of the winner of a competition

roughly

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US / ˈrʌfli /

UK / ˈrʌflɪ /

B1
  • adverb
  • Approximately; (of numbers) about; around
  • In a manner that is violent or not careful
  • In an inexact, imprecise or violent way
  • In a basic, simple manner

notation

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US / nəʊ'teɪʃn /

UK / noˈteʃən /

C2
  • noun
  • Set of written signs are used in music or math

own

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US / əʊn /

UK / on /

A1
  • adjecitve
  • Belong to oneself
  • determiner
  • Yours, his, hers, etc.; not belonging to another
  • pronoun
  • (Something) belong to myself
  • verb
  • To have something as your property
  • Subtitles section
  • Whether you like it or not, we use numbers every day.
  • Some numbers, such as the speed of sound, are small and easy to work with.
  • Other numbers, such as the speed of light, are much larger and cumbersome to work with.
  • We can use scientific notation to express these large numbers in a much more manageable format.
  • So we can write 299,792,458 meters per second as 3.0 times 10 to the eighth meters per second.
  • Correct scientific notation requires that the first term range in value so that it is greater than one but less than 10, and the second term represents the power of 10 or order of magnitude by which we multiply the first term.
  • We can use the power of 10 as a tool in making quick estimations when we do not need or care for the exact value of a number.
  • For example, the diameter of an atom is approximately 10 to the power of negative 12 meters.
  • The height of a tree is approximately 10 to the power of one meter.
  • The diameter of the Earth is approximately 10 to the power of seven meters.
  • The ability to use the power of 10 as an estimation tool can come in handy every now and again, like when you're trying to guess the number of M&M's in a jar, but is also an essential skill in math and science,
  • especially when dealing with what are known as Fermi problems.
  • Fermi problems are named after the physicist Enrico Fermi, who's famous for making rapid order-of-magnitude estimations, or rapid estimations, with seemingly little available data.
  • Fermi worked on the Manhattan Project in developing the atomic bomb, and when it was tested at the Trinity site in 1945, Fermi dropped a few pieces of paper during the blast and used the distance they traveled backwards as they fell to estimate the strength of the explosion as 10 kilotons of TNT,
  • which is on the same order of magnitude as the actual value of 20 kilotons.
  • One example of the classic Fermi estimation problems is to determine how many piano tuners there are in the city of Chicago, Illinois.
  • At first, there seem to be so many unknowns that the problem appears to be unsolvable.
  • That is the perfect application for a power-of-10 estimation, as we don't need an exact answer - an estimation will work.
  • We can start by determining how many people live in the city of Chicago.
  • We know that it is a large city, but we may be unsure about exactly how many people live in the city.
  • Are the one million people? Five million people?
  • This is the point in the problem where many people become frustrated with the uncertainty, but we can easily get through this by using the power of 10.
  • We can estimate the magnitude of the population of Chicago as 10 to the power of six.
  • While this doesn't tell us exactly how many people live there, it serves an accurate estimation for the actual population of just under three million people.
  • So if there are approximately 10 to the sixth people in Chicago, how many pianos are there?
  • If we want to continue dealing with orders of magnitude, we can either say that one out of 10 or one out of one hundred people own a piano.
  • Given that our estimate of the population includes children and adults, we'll go with the latter estimate, which estimates that there are approximately 10 to the fourth, or 10,000 pianos, in Chicago.
  • With this many pianos, how many piano tuners are there?
  • We could begin the process of thinking about how often the pianos are tuned, how many pianos are tuned in one day, or how many days a piano tuner works, but that's not the point of rapid estimation.
  • We instead think in orders of magnitude, and say that a piano tuner tunes roughly 10 to the second pianos in a given year, which is approximately a few hundred pianos.
  • Given our previous estimate of 10 to the fourth pianos in Chicago, and the estimate that each piano tuner can tune 10 to the second pianos each year, we can say that there are approximately 10 to the second piano tuners in Chicago.
  • Now, I know what you must be thinking: How can all of these estimates produce a reasonable answer?
  • Well, it's rather simple.
  • In any Fermi problem, it is assumed that the overestimates and underestimates balance each other out, and produce an estimation that is usually within one order of magnitude of the actual answer.
  • In our case we can confirm this by looking in the phone book for the number of piano tuners listed in Chicago.
  • What do we find? 81.
  • Pretty incredible, given our order-of-magnitude estimation.
  • But, hey - that's the power of 10.