Subtitles section
Repeat sentence
Subtitles mode
Full screen
Previous
Next
x 1.0
Playback speed
More

Radius of observable universe (correction) | Cosmology & Astronomy | Khan Academy

Video vocabulary

big

Copy vocabulary

US / bɪɡ /

UK / bɪɡ /

A1
  • adjecitve
  • Popular
  • Serious
  • Large

little

Copy vocabulary

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

Copy vocabulary

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

this

Copy vocabulary

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

kind

Copy vocabulary

US / kaɪnd /

UK / kaɪnd /

A1
  • adjecitve
  • In a caring and helpful manner
  • friendly and considerate
  • noun
  • One type of thing

year

Copy vocabulary

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

Copy vocabulary

US / jʊ /

UK / ju /

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

make

Copy vocabulary

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

universe

Copy vocabulary

US / ˈju:nɪvɜ:s /

UK / ˈjunəˌvɚs /

B2
  • noun
  • All of space that contains planets and stars
  • Things surrounding a person, affecting their life

where

Copy vocabulary

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

leave

Copy vocabulary

US / li:v /

UK / liv /

A1
  • noun
  • Permission to do something
  • Vacation time; time off work
  • verb
  • To go away from; depart
  • To gift property to someone after you die
  • To allow something to continue happening
  • To let something remain unused or available
  • To let something or someone remain somewhere

approximately

Copy vocabulary

US / əˈprɒksɪmətli /

UK / əˈprɑksəmɪtlɪ /

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

something

Copy vocabulary

US / ˈsʌmθɪŋ /

UK / ˈsʌmθɪŋ /

A1
  • adverb
  • In some degree or measure
  • noun
  • a person or thing of some value or consequence
  • pronoun
  • Thing that is not yet known or named
  • Approximately

keep

Copy vocabulary

US / ki:p /

UK / kip /

A1
  • noun
  • Large, strong tower in the middle of a castle
  • Money spent on you so you can live in a place
  • verb
  • To continue doing something; not to stop
  • To stop balls going in a goal in sports
  • To not give back or return something
  • (Of food) to not spoil or not rot
  • To take possession of something to own, e.g. a pet
  • To have and continue to hold something
  • To do something that you have promised or agreed
  • To stay in a certain place or condition
  • To maintain the rules

over

Copy vocabulary

US / 'əʊvə(r) /

UK / ˈovɚ /

A1
  • adverb
  • Finished; no longer happening
  • Towards the ground/away from a standing position
  • noun
  • A set of six consecutive balls bowled in cricket
  • other
  • Finished
  • preposition
  • Showing the relation when a thing is above another
  • On or covering something
  • Above or across something
  • More than you need
  • From one side to the other
  • In the direction of; toward

from

Copy vocabulary

US / frəm /

UK / frʌm, frɑm,frəm /

A1
  • preposition
  • Starting at a particular place, time or level

only

Copy vocabulary

US / ˈəunli /

UK / ˈonli /

A1
  • adverb
  • Just one; just that amount or thing; not more than
  • Not very important or serious
  • Just that type of thing, person
  • Short time ago; not before a certain time
  • conjunction
  • Except; but

photon

Copy vocabulary

US / ˈfəʊtɒn /

UK / ˈfoʊtɑ:n /

B2
  • noun
  • Particle with energy but no mass, electric charge

affect

Copy vocabulary

US / ə'fekt /

UK / əˈfɛkt /

A2
  • verb
  • To cause a change in something else

hopefully

Copy vocabulary

US / ˈhəʊpfəli /

UK / ˈhopfəli /

A2
  • adverb
  • In a manner wishing something to happen

and

Copy vocabulary

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

hey

Copy vocabulary

US / heɪ /

UK / he /

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

think

Copy vocabulary

US / θɪŋk /

UK / θɪŋk /

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

precision

Copy vocabulary

US / prɪˈsɪʒn /

UK / prɪˈsɪʒən /

A2
  • adjecitve
  • Performed in a very careful, detailed manner
  • noun
  • Quality of being very accurate and exact

affair

Copy vocabulary

US / ə'feə(r) /

UK / əˈfɛr /

A2
  • noun
  • Secret sexual relationship between two people
  • Event or a set of events, often unpleasant ones

away

Copy vocabulary

US / ə'weɪ /

UK / əˈwe /

A1
  • adjecitve
  • Not present
  • adverb
  • Disappear completely
  • Doing something with a lot of energy
  • Not here; far from here; in a different direction
  • To a different area, location

clear

Copy vocabulary

US / klɪə(r) /

UK / klɪr /

A1
  • adjecitve
  • Empty; without anything in it or on it
  • Being certain and without doubt
  • Being without any streaks, spots, or cracks
  • Easy to understand; well-explained; obvious
  • adverb
  • Completely; entirely; through the whole of
  • Away from; free from
  • verb
  • To recover from or remove a problem
  • To get rid of the entire contents of
  • To give permission for something to happen
  • To make a place or surface empty by removing
  • To prove that someone is not guilty or to blame

have

Copy vocabulary

US / həv /

UK / hæv /

A1
  • verb
  • To drink, smoke, eat or use something
  • To experience the effects of something
  • To organize an event, or join in an activity
  • To own, possess, or hold something
  • To cause to happen or produce a particular effect

last

Copy vocabulary

US / lɑ:st /

UK / læst /

A1
  • adjecitve
  • Most recent; the latest
  • The one before
  • adverb
  • Final; with nothing following; after all others
  • Most recent; the latest
  • determiner
  • The one at the end
  • verb
  • To remain or continue for a certain period of time

many

Copy vocabulary

US / 'menɪ /

UK / ˈmɛni /

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

after

Copy vocabulary

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

actually

Copy vocabulary

US / ˈæktʃuəli /

UK / ˈæktʃuəli /

A1
  • adverb
  • Used to add new (often different) information

should

Copy vocabulary

US / ʃʊd /

UK / ʃʊd /

A1
  • other
  • Used to indicate what is proper or reasonable

obviously

Copy vocabulary

US / ˈɒbviəsli /

UK / ˈɑːbviəsli /

A2
  • adverb
  • In a way that is obvious/easy to see or understand

million

Copy vocabulary

US / ˈmɪljən /

UK / ˈmɪljən /

A1
  • number
  • 1,000,000

sure

Copy vocabulary

US / ʃʊə(r) /

UK / ʃʊr /

A1
  • adjecitve
  • Having no doubts about something
  • Have confidence in your own words or actions
  • Firmly established or held; being firm or stable
  • Being correct or true
  • adverb
  • What you say to agree willingly

point

Copy vocabulary

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

quick

Copy vocabulary

US / kwɪk /

UK / kwɪk /

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

here

Copy vocabulary

US / hɪə(r) /

UK / hɪr /

A1
  • adverb
  • In this place; at this location, position or time

too

Copy vocabulary

US / tu: /

UK / tu /

A1
  • adverb
  • In addition, also; with emphasis
  • Say that something is more than you want

number

Copy vocabulary

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

enough

Copy vocabulary

US / ɪˈnʌf /

UK / ɪˈnʌf /

A1
  • adjecitve
  • Sufficient to answer the need
  • adverb
  • To a satisfactory degree
  • pronoun
  • Equal to what is needed; as much as required
  • Adequate number or amount

expand

Copy vocabulary

US / ɪk'spænd /

UK / ɪkˈspænd /

A2
  • verb
  • To make something larger in size, number, amount

bang

Copy vocabulary

US / bæŋ /

UK / bæŋ /

A2
  • noun
  • Sudden loud noise, as when a bomb explodes
  • A loud noise
  • verb
  • To strike something loudly or forcefully

that

Copy vocabulary

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

Copy vocabulary

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

even

Copy vocabulary

US / 'i:vn /

UK / ˈivən /

A1
  • adjecitve
  • Being equal in influence, power, possibility etc.
  • Being divided equally or fairly
  • (Of teams/contest) with similar chances of success
  • Smooth, level, or regular
  • Can be divided by 2; ending in 2, 4, 6, 8, or 0
  • At a regular, equally steady manner
  • Remaining steady and unchanging
  • adverb
  • (When this is surprising) as well; too
  • (Used to compare two things/stress the difference)
  • verb
  • To make something level; to flatten
  • To make something equal

current

Copy vocabulary

US / 'kʌrənt /

UK / ˈkɚrənt, ˈkʌr- /

A2
  • adjecitve
  • Happening or being in the present time
  • noun
  • Electricity flowing through wires
  • Movement of water in a river, or air in the sky

about

Copy vocabulary

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)

right

Copy vocabulary

US / raɪt /

UK / raɪt /

A1
  • adjecitve
  • Correct or true
  • The south side of you looking at the rising sun
  • adverb
  • Exactly in a place or time
  • Being appropriate for a particular event
  • In a straight or direct manner
  • noun
  • Something you are legally or morally allowed to do
  • Ideal of what is just and good
  • Political view based on conservatism
  • verb
  • To fix something previously wrong or unjust
  • To make upright, as a boat that has turned over

observable

Copy vocabulary

US / əbˈzɜ:vəbl /

UK / əbˈzɚvəbəl /

B1
  • adjecitve
  • Being able to be seen, noticed, or sensed

happen

Copy vocabulary

US / 'hæpən /

UK / ˈhæpən /

A1
  • verb
  • To take place or occur

incorrectly

Copy vocabulary

US / ˌɪnkə'rektlɪ /

UK / ˌɪnkə'rektlɪ /

B1
  • adverb
  • In a way that is incorrect or wrong

understanding

Copy vocabulary

US / ˌʌndəˈstændɪŋ /

UK / ˌʌndərˈstændɪŋ /

A1
  • adjecitve
  • Being sympathetic
  • noun
  • When you get the meaning correctly; comprehension
  • Knowledge about something or someone
  • verb
  • To know the meaning of language, what someone says

place

Copy vocabulary

US / pleɪs /

UK / ples /

A1
  • noun
  • Particular location, area or region
  • verb
  • To put someone in a particular type of situation
  • To put something in a certain location or position

then

Copy vocabulary

US / ðen /

UK / ðɛn /

A1
  • adverb
  • A time that is not now
  • Following another thing in time or arrangement
  • Following on reasonably from what was just stated
  • At that time, not now

hard

Copy vocabulary

US / hɑ:d /

UK / hɑː(r)d /

A1
  • adjecitve
  • Difficult to do; difficult to understand
  • (Of facts) not able to be misunderstood; clear
  • (Of alcohol) strong
  • Involving or requiring lots of work, effort, care
  • Being full of pain, trouble, and problems
  • Strong
  • (Of edge) clear; sharp
  • Difficult to bend, break or cut; solid
  • adverb
  • With lots of force, power, or impact

get

Copy vocabulary

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

video

Copy vocabulary

US / 'vɪdɪəʊ /

UK / ˈvɪdiˌo /

A2
  • adjecitve
  • Of a moving film, with sound
  • noun
  • Recording capturing action with sound
  • verb
  • To make a moving film of, with sound

want

Copy vocabulary

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

significant

Copy vocabulary

US / sɪgˈnɪfɪkənt /

UK / sɪɡˈnɪfɪkənt /

A2
  • adjecitve
  • Large enough to be noticed or have an effect
  • Having meaning; important; noticeable
  • (Statistics) being clearly different

would

Copy vocabulary

US / wʊd /

UK / wʊd /

A1
  • other
  • Used to indicate something imagined
  • Used to ask or request something politely
  • Verb used to indicate possibility, request etc.
  • Used to indicate a preference
  • Used to indicate a reaction
  • Indicates something that occurred repeatedly
  • Used to indicate willingness or ability to do

understand

Copy vocabulary

US / ˌʌndə'stænd /

UK / ˌʌndɚˈstænd /

A1
  • verb
  • To know the meaning of language, what someone says

really

Copy vocabulary

US / ˈri:əli /

UK / ˈriəˌli, ˈrili /

A1
  • adverb
  • Used to stress something that is said; definitely
  • In a true or accurate manner
  • Very

but

Copy vocabulary

US / bət /

UK / bʌt,bət /

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

now

Copy vocabulary

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

maybe

Copy vocabulary

US / ˈmeɪbi /

UK / ˈmebi /

A1
  • adverb
  • Possibly but not certainly; perhaps

our

Copy vocabulary

US / 'aʊə(r) /

UK / aʊr /

A1
  • determiner
  • Belonging to us

not

Copy vocabulary

US / nɒt /

UK / nɑt /

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

digit

Copy vocabulary

US / ˈdɪdʒɪt /

UK / ˈdɪdʒɪt /

B2
  • noun
  • Person's finger or toe
  • Written symbol of the numbers from 0 to 9

bit

Copy vocabulary

US / bɪt /

UK / bɪt /

A1
  • noun
  • Device put in a horse's mouth to control it
  • Small piece of something
  • verb
  • (E.g. of fish) to take bait and be caught

error

Copy vocabulary

US / ˈerə(r) /

UK / ˈɛrɚ /

A2
  • noun
  • Something that is not correct; a mistake

billion

Copy vocabulary

US / ˈbɪljən /

UK / ˈbɪljən /

A2
  • noun
  • Number 1,000,000,000

travel

Copy vocabulary

US / ˈtrævl /

UK / ˈtrævəl /

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

space

Copy vocabulary

US / speɪs /

UK / spes /

A1
  • noun
  • Empty area kept for a specific reason, like a car
  • Empty area with nothing in it
  • Area in the sky where the stars are
  • Area between written words on a page
  • verb
  • To make a certain distance or time between

change

Copy vocabulary

US / tʃeɪndʒ /

UK / tʃendʒ /

A1
  • noun
  • Exchange of one set of clothes for another
  • Money in the form of coins instead of paper
  • Money returned after giving too much
  • Act of making or becoming something else
  • verb
  • To exchange one set of clothes for another
  • To exchange one kind of money for another
  • To replace something with another thing
  • To make or become something else
  • To go from one train, bus, etc. and go to another

slight

Copy vocabulary

US / slaɪt /

UK / slaɪt /

B1
  • adjecitve
  • Small (amount, quality)
  • Appearing thin, delicate and physically weak
  • noun
  • Rude and disrepectful treatment
  • verb
  • To ignore or treat rudely and with no respect

take

Copy vocabulary

US / teɪk /

UK / tek /

A1
  • noun
  • Filming of a single scene for TV or the movies
  • verb
  • To accept something that is offered
  • To use a method of traveling, e.g. a bus or train
  • To use a camera to make (a photo)
  • To pick up something and go away with it
  • To study a subject in school
  • To attempt to pass (an exam)
  • To require a certain amount of time, money, space

ago

Copy vocabulary

US / əˈgəʊ /

UK / əˈgoʊ /

A1
  • adverb
  • At a specified length of time in the past

all

Copy vocabulary

US / ɔ:l /

UK / ɔl /

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

correct

Copy vocabulary

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

talk

Copy vocabulary

US / tɔ:k /

UK / tɔk /

A1
  • noun
  • Style of speaking
  • Discussion between two countries
  • Giving information in front of people; lecture
  • Saying things or ideas to someone with words
  • verb
  • To make a formal speech about something
  • To say things or ideas to someone with words

just

Copy vocabulary

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)

math

Copy vocabulary

US / mæθ /

UK / mæθ /

A2
  • noun
  • Study or science of numbers and shapes

light

Copy vocabulary

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

much

Copy vocabulary

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

decimal

Copy vocabulary

US / 'desɪml /

UK / ˈdɛsəməl /

B2
  • noun
  • Number using one equal tenth of a whole as a basis

traverse

Copy vocabulary

US / trəˈvɜ:s /

UK / trəˈvɜ:rs /

B2
  • verb
  • To pass across, over, or through

start

Copy vocabulary

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

state

Copy vocabulary

US / steɪt /

UK / stet /

A1
  • adjecitve
  • Concerning region within a country
  • noun
  • Region within a country, with its own government
  • Situation or condition something is in
  • verb
  • To say; declare as fact

less

Copy vocabulary

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

answer

Copy vocabulary

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

than

Copy vocabulary

US / ðən /

UK / ðən /

A1
  • conjunction
  • Used to compare two things that are not equal
  • Subtitles section
  • I want to make a quick correction to the last video.
  • It doesn't really affect the learning of the last video.
  • But I just want to make sure that you understand that I got the math a little bit wrong in the last video.
  • I said that you had this state, 300,000 years.
  • So we talk about the Big Bang happening 13.7 billion years ago.
  • And then I talk about this state of affairs where we're maybe 30 million light years away from the edge of the observable universe, the current observable universe.
  • And I said that this was about 300,000 years after the Big Bang.
  • That's what I talked about in the last video.
  • That was our starting point when the photon started leaving that point.
  • And obviously, the universe kept expanding.
  • The photon, it kind of traversed more and more.
  • But still had more and more to travel as the universe expanded, as all of space expanded.
  • But this is 300,000 years after the Big Bang.
  • Now my brain, because I was kind of not thinking hard enough about it, I said, hey, this was 13.4 billion years ago.
  • That's what I incorrectly said in the last video.
  • I said that this is 13.4 billion years ago.
  • That's what I said in the last video.
  • And that is wrong.
  • Because if this was 13.4 billion years ago, this would have been 300 million years after the Big Bang.
  • We were talking about only 300,000 years after the Big Bang.
  • So it wouldn't have taken that many decimal places off of something in the billions.
  • The correct answer is this would have been only a little less than 13.7 billion years.
  • It actually wouldn't have even made a significant digit.
  • So this is still approximately 13.7 billion years ago.
  • So I wanted to just make that correction.
  • It was a slight error.
  • I shouldn't have viewed this as 0.3 billion years.
  • This is only 0.3 million years.
  • It doesn't even basically change the precision on this number right over here.
  • So I just wanted to clear that up.
  • But hopefully, it doesn't affect your understanding too much.