Are there universal expressions of emotion? - Sophie Zadeh

Learn more about TED-Ed Clubs here: bit.ly/2z8YFSo
View full lesson: ed.ted.com/lessons/are-there-...
The 40 or so muscles in the human face can be activated in different combinations to create thousands of expressions. But do these expressions look the same and communicate the same meaning around the world regardless of culture? Is one person’s smile another’s grimace? Sophie Zadeh investigates.
Lesson by Sophie Zadeh, animated by Estúdio Bacuri.
Thank you so much to our patrons for your support! Without you, this video would not be possible! Abhijit Kiran Valluri, Mandeep Singh, Sama aafghani, Vinicius Lhullier, Connor Wytko, Marylise CHAUFFETON, Marvin Vizuett, Jayant Sahewal, Quinn Shen, Caleb ross, Elnathan Joshua Bangayan, Gaurav Rana, Mullaiarasu Sundaramurthy, Jose Henrique Leopoldo e Silva, Dan Paterniti, Jose Schroeder, Jerome Froelich, Tyler Yoshizumi, Martin Stephen, Justin Carpani, Faiza Imtiaz, Khalifa Alhulail, Tejas Dc, Govind Shukla, Srikote Naewchampa, Ex Foedus, Sage Curie, Exal Enrique Cisneros Tuch, Vignan Velivela, Ahmad Hyari, A Hundred Years, eden sher, Travis Wehrman, Minh Tran, Louisa Lee, Kiara Taylor, Hoang Viet, Nathan A. Wright, Jast3r , Аркадий Скайуокер, Milad Mostafavi, Singh Devesh Sourabh, Ashley Maldonado, Clarence E. Harper Jr., Bojana Golubovic, Mihail Radu Pantilimon, Sarah Yaghi, Benedict Chuah, Karthik Cherala, haventfiguredout, Violeta Cervantes, Elaine Fitzpatrick, Lyn-z Schulte, cnorahs, Henrique 'Sorín' Cassús, Tim Robinson, Jun Cai, Paul Schneider, Amber Wood, Ophelia Gibson Best, and Cas Jamieson.

Пікірлер: 232

  • @TEDEd
    @TEDEd6 жыл бұрын

    Connect with fellow students around the world through TED-Ed's student ideas program: bit.ly/2z8YFSo Share your ideas on the TED platform and see just how much we have in common.

  • @Rokku6666

    @Rokku6666

    6 жыл бұрын

    bucharest is in Romania , not Hungary

  • @TEDEd

    @TEDEd

    6 жыл бұрын

    Yes, thank you Berserker Mushroom. We are currently editing the video to make this fix and will be replacing it soon.

  • @Horcrux1997

    @Horcrux1997

    6 жыл бұрын

    Hey, interesting video. I really liked the way in wich the content was presented and the graphics, but, just to let you know.. Bucharest is Romania's capital, not Hungary's. Hungary's capital is Budapest.

  • @Horcrux1997

    @Horcrux1997

    6 жыл бұрын

    didn't see the preview comment.

  • @thebrilliant196

    @thebrilliant196

    6 жыл бұрын

    Our facial musle and eyes brow do the work of showing an expression, but I thought before that our eyes and way of talking shows it, and also had a confusion in that, thanks for helping me out, Ted-ed really has great teachers I wish I had one to teach me

  • @11jokerchen11
    @11jokerchen116 жыл бұрын

    "But if you ever find yourself among strangers in a strange land, a friendly smile could go a long way" is such a beautiful sentiment ❤️

  • @TECHASPIRANT

    @TECHASPIRANT

    6 жыл бұрын

    Wow well said...

  • @TR-ru7wl
    @TR-ru7wl6 жыл бұрын

    Did anyone else imitate the different core expressions as she went through them?

  • @itstrollpaul4322

    @itstrollpaul4322

    6 жыл бұрын

    The Raff yeahh

  • @colleen9493

    @colleen9493

    6 жыл бұрын

    No

  • @MegaMGstudios

    @MegaMGstudios

    6 жыл бұрын

    Ye

  • @nerdstark9002

    @nerdstark9002

    6 жыл бұрын

    ye

  • @jackspank9521

    @jackspank9521

    5 жыл бұрын

    Yeah

  • @JeagerTv
    @JeagerTv6 жыл бұрын

    I'm a huge fan of the stop-motion here

  • @CuriosityCulture
    @CuriosityCulture6 жыл бұрын

    I learned the hard way that when I did something wrong, and my mom smiled, I was done for.

  • @Amitdas-gk2it

    @Amitdas-gk2it

    6 жыл бұрын

    Hsi nhi aai iss baar

  • @htoodoh5770

    @htoodoh5770

    6 жыл бұрын

    Harshil Patel lol

  • @kevinhuang8916

    @kevinhuang8916

    6 жыл бұрын

    Oof

  • @maddiedhiya9659

    @maddiedhiya9659

    6 жыл бұрын

    Harshil Patel you're everywhere

  • @HiAdrian

    @HiAdrian

    6 жыл бұрын

    *@Maddie Dhiya:* Male equivalent of *Science with Katie* - fishing for views/subs.

  • @Rombododecaedron
    @Rombododecaedron6 жыл бұрын

    The video is really cool! The nice work of talented visualizers (and sound designers :)

  • @Yathuprem
    @Yathuprem6 жыл бұрын

    This is like the first time i saw a no animated TED Ed video. Awesome btw

  • @loleq2137

    @loleq2137

    6 жыл бұрын

    Yathu prem wot in tarnation 😤 r u blind or what 👀 I feel offended as a stopmotion animator 😤 this is stopmotion ni🅿🅱🅾🆖🅱a

  • @suhkawnit
    @suhkawnit6 жыл бұрын

    I’ve been wondering about this exact topic for a while now. I agree, certain emotions are associated with universal facial expressions. Others are learned from the society we live in. For example, some people roll their eyes when they’re annoyed, but that’s something we’ve picked up in movies and TV.

  • @dcllaw677
    @dcllaw6776 жыл бұрын

    Here is a possibility Expression may be universal, but the cultural norms of what expression is appropriate, and when it is appropriate, are highly variable.

  • @oppablu105

    @oppablu105

    6 жыл бұрын

    David Lucey Exactly. Men for example are less likely to show emotions in certain areas than others because it's frowned upon.

  • @Kritatutorials
    @Kritatutorials2 жыл бұрын

    This is amazing thank you so much for the in-depth analysis

  • @nicolasotero5555
    @nicolasotero55556 жыл бұрын

    I am a simple man, I see a Ted ed notification, I click

  • @jazy9137

    @jazy9137

    6 жыл бұрын

    Nicolás Otero no you are a fox :/

  • @Legend-ls3rm

    @Legend-ls3rm

    6 жыл бұрын

    Nicolás Otero no sir you are a genius

  • @patrickteetzen1218

    @patrickteetzen1218

    5 жыл бұрын

    Nicolás Otero h Hfmmfrztzh lunch coffee byvg

  • @Krl03

    @Krl03

    5 жыл бұрын

    oof big mood

  • @alecmatthewgranados7300
    @alecmatthewgranados73006 жыл бұрын

    Ted Ed I LOVE the way you explain things so much. I'm not even big on science but I'll happily watch any science video you make.

  • @steffeeH
    @steffeeH6 жыл бұрын

    To clarify, not all facial expressions are universal - there are 6 facial expressions that are academically considered universal, and further 3 that could be universal as well - but the rest may vary by culture, region, and/or personality.

  • @lordgrim9779

    @lordgrim9779

    Жыл бұрын

    ^this. They didn't mention a few of the more contemporary studies that found a greater variance of nuance among indigenous tribes where they viewed "fear" expressions as aggression for example. Even the universal expressions are under the microscope due to new information.

  • @gaiabhmandresen3192
    @gaiabhmandresen31926 жыл бұрын

    Some of you might recognize five of the six core emotions, as they can be seen in Pixar’s ‘Inside Out’. 'Surprise' was removed since it was too close to their version of Fear.

  • @CaptainPIanet
    @CaptainPIanet6 жыл бұрын

    These are the types of videos I like to watch over my lunch break

  • @elliotyong2331
    @elliotyong23316 жыл бұрын

    This is why blind people can smile despite never seeing one before

  • @StrangerHappened
    @StrangerHappened6 жыл бұрын

    *IT IS AMAZING* that even the scientific part of humanity was so dense that it has required like hundreds of years to understand that some basic emotions have built-in face expressions. Just witnessing abandoned newborn babies or blind-from-birth people could have made it clear that e.g. smiling has nothing to do with taught behaviours. No one has ever really smiled for them, and yet the babies know how to smile and it does express joy.

  • @Upgradezz

    @Upgradezz

    6 жыл бұрын

    Stranger Happened exactly.

  • @Choshmeesh

    @Choshmeesh

    2 жыл бұрын

    Science is not just accepting common sense as truth. Science is testing out a hypotheses and trying to disprove it and reproduce results multiple times and more things I dont yet know, to prove/disprove theories/hypotheses. I understand what you meant by your comment, but science just can not work totally on common sense and hence they had to be sure before saying "this is the truth, according the research conducted, and data collected"

  • @sebastianelytron8450
    @sebastianelytron84506 жыл бұрын

    The only universal is that people can't judge you if you don't emote 😶

  • @Future_Pheonix

    @Future_Pheonix

    6 жыл бұрын

    Sebastian Elytron Well, you're in luck if your resting face doesn't evoke the incredibly annoying question of "why are you sad"? or make people ask you to smile 😑😒 People used to do that to me all the time...

  • @chrispo7610

    @chrispo7610

    6 жыл бұрын

    LandAhoy same

  • @kingplunger6033

    @kingplunger6033

    6 жыл бұрын

    LandAhoy y, just happened to me 5 min ago

  • @Future_Pheonix

    @Future_Pheonix

    6 жыл бұрын

    My condolences 😩 I hope you found time to rest your face muscles since then...

  • @jjsmith706

    @jjsmith706

    5 жыл бұрын

    Wrong. People judge you more harshly if you don't.

  • @alriefkywalangadi3873
    @alriefkywalangadi38736 жыл бұрын

    I just love how ted ed have diverse animation styles

  • @johnnybadboy3475
    @johnnybadboy34756 жыл бұрын

    Pretty neat animation. I love the flipbook/hamburglar switch pages.

  • @SwaroopKadaba
    @SwaroopKadaba6 жыл бұрын

    Anyone else trying out the different facial expressions? 😂

  • @johnedeldoctor1484

    @johnedeldoctor1484

    6 жыл бұрын

    Swaroop Kadaba yes 😁

  • @luisg.ontoriaalvarez2334
    @luisg.ontoriaalvarez23346 жыл бұрын

    Hi people, how can I get the transcription of this video?

  • @pandaapanda7627
    @pandaapanda76276 жыл бұрын

    Amazing video!! Love the animation!! 😜♥♥

  • @gjugany
    @gjugany6 жыл бұрын

    I'm in love with the animation.

  • @hellogoodbyeandallinbetween
    @hellogoodbyeandallinbetween5 жыл бұрын

    Amazing video, so informative and awesome animation

  • @sueg2658
    @sueg26586 жыл бұрын

    And then add body movement to the mix of expressing emotions, conscious or not and WOW!

  • @mot1215
    @mot12156 жыл бұрын

    Really love this animations!

  • @Freaksoftheinternet
    @Freaksoftheinternet6 жыл бұрын

    I would have guessed that emotional expressions are essentially universal because when you become really happy, you kinda can't help but smile. You definitely don't always consciously choose to smile (or make any other facial expression for that matter), which means there's something innate about it that none of us "learned" as a result of culture or surroundings.

  • @chrispo7610
    @chrispo76106 жыл бұрын

    Amazing!

  • @beytullahberk3632
    @beytullahberk36326 жыл бұрын

    I need to study or the teacher will show me an expression I won't like

  • @huriamazhar6983
    @huriamazhar69836 жыл бұрын

    Another great video by ted ed.Keep the good work up.😃😃😄

  • @seanmundy9829
    @seanmundy98296 жыл бұрын

    Because of Dr. Eckman's research and contribution to emotional psychology, we now have the amazing modern classic that is "Inside Out."

  • @julioromanlopez8311
    @julioromanlopez83116 жыл бұрын

    TED-Ed if you are going to talk about EMOTIONS you should've brought David Cage, because he is the creator of EMOTIONS and also he knows how many EMOTIONS are in a polygon (he also met Ellen Page who is an actress because she told him about it)

  • @Bhavishtraders
    @Bhavishtraders6 жыл бұрын

    Amazing animation

  • @nelliholm3717
    @nelliholm37176 жыл бұрын

    This was really interesting!

  • @tinotrivino
    @tinotrivino5 жыл бұрын

    There are two Types of Emotional Facial Expressions. The cultural learned, and the Instinct like disgust, sadness, fear etc! Video is correct.

  • @paradoxine6287
    @paradoxine62876 жыл бұрын

    AYY GREAT VID

  • @mjstory1976
    @mjstory19766 жыл бұрын

    Awesome and informative video

  • @snowcold5932
    @snowcold59326 жыл бұрын

    Really cool video, and a great animation style :D PS: You wrote "Bucharest, Hungary" at the end, I think you meant Budapest

  • @TECHASPIRANT

    @TECHASPIRANT

    6 жыл бұрын

    Plz help me to increase my viewers

  • @SupahNinjasfreak

    @SupahNinjasfreak

    6 жыл бұрын

    TECH ASPIRANT .-.

  • @njstuckey

    @njstuckey

    6 жыл бұрын

    Or they meant "Bucharest, Romania."

  • @sourcedrop7624
    @sourcedrop76246 жыл бұрын

    Facial expression is the result of energy movement, including direction, intensity, and open/closedness through our nonphysical energy centers (aka chakras). The nonphysical is intimately connected to the physical counterpart.

  • @pepsdeps
    @pepsdeps5 жыл бұрын

    Man, I love TEDed.

  • @hasnain9654
    @hasnain96546 жыл бұрын

    Are these videos really made with After Effects? I have downloaded but wasn't sure it was so creative.

  • @rania9534
    @rania95346 жыл бұрын

    Once when I was little and my sister was a baby I asked my mother if she was sure that when the baby smiled it was happy and when it cried it wasn’t. It could be that the baby was sad and smiling we think it is happy. I think I knew that expressions are universal till then

  • @ToddyMichael
    @ToddyMichael6 жыл бұрын

    Expressions of learning something new :)

  • @Dr_Steve.N
    @Dr_Steve.N6 жыл бұрын

    You do good videos

  • @aakashkishore1525
    @aakashkishore15256 жыл бұрын

    Omg how hard it would have been to make such a video

  • @notsure5145
    @notsure51456 жыл бұрын

    1 minute. Wow. I really am always on KZread

  • @kamilalikamil4229

    @kamilalikamil4229

    6 жыл бұрын

    but youre not sure

  • @notsure5145

    @notsure5145

    6 жыл бұрын

    faded shades ... right

  • @Milestonemonger
    @Milestonemonger6 жыл бұрын

    A smile is universal.

  • @saileshsingh7661
    @saileshsingh76616 жыл бұрын

    Love the stopmotion😊

  • @arontisoczki5956
    @arontisoczki59566 жыл бұрын

    4:30 “Bucharest, Hungary” Good job on your research there TED-Ed!

  • @sitin8535
    @sitin85356 жыл бұрын

    Directly remind me of Paul Ekmannn

  • @jedimmj11
    @jedimmj116 жыл бұрын

    You totally glossed over the whole varying of intensity between cultures bit

  • @gabrielajo2972
    @gabrielajo29726 жыл бұрын

    I see what you did there in selecting your characters, Inside Out! (The core emotions identified here from scientific studies are exactly the major characters that the movie follows).

  • @seandaniel3380
    @seandaniel33806 жыл бұрын

    First to comment and man i was just watching ted ed ! Love u guys😙

  • @doctorrekha
    @doctorrekha Жыл бұрын

    However, as an Ayurvedic doctor, I can say that, explicitly expressing emotions for a long time can do more harm than good. For example, Ayurveda mentions 4 emotions that affects digestion - Sadness, Overthinking, Fear, Anger and expressing these emotions explicitly can lead to digestion related issues. And according to Ayurveda, every disease is due to a bad Agni a.k.a gut health. So to take care of your health, one must have control over one’s emotions.

  • @jaro3495
    @jaro34953 жыл бұрын

    wie is hier voor mr ringoot

  • @fotoperfotoland3721

    @fotoperfotoland3721

    3 жыл бұрын

    Hey jaro

  • @kaydergator
    @kaydergator2 жыл бұрын

    It would be well worth it to check out “How Emotions are made” by Lisa Feldman Barrett for additional perspectives about this topic.

  • @mta136
    @mta1366 жыл бұрын

    The city in Saudi Arabia is called Dammam, not Damman. Thanks for a great video!

  • @Sam-ey1nn
    @Sam-ey1nn6 жыл бұрын

    Anyone who has ever had a baby knows the facial expressions are the first and most important tool humans use to communicate with each other. A baby's smile is one of the first (and one of the best) milestones they reach.

  • @MJ-cq6gz
    @MJ-cq6gz6 жыл бұрын

    At my church, the bassist in the worship team is from Siberia. My dad was visiting my church for the first time, and he asked me if she was Russian, because there was something about her facial expression that "seemed Russian." We figured out that it was her smile. It seemed "off" to us. I've read that Russian culture discourages smiling, but American churches (in my experience) encourage big smiles from anyone up front, so she was maybe trying to imitate an expression that she had repressed most of her life. I wonder if there are other situations where culture affects how universal emotions are expressed, e.g., through taboos on certain expressions?

  • @jedimmj11
    @jedimmj116 жыл бұрын

    I feel like an analysis of emojis in light of this is in order

  • @hannahnr97
    @hannahnr976 жыл бұрын

    Ted ed!!

  • @elmosanica
    @elmosanica6 жыл бұрын

    Now I wonder if theres such universal micro expression or not, because details like eyes can be interpreted wrong by people. For instance eyes that focusing and thinking are pretty similar to eyes that focusing and angry.

  • @yearoldvampire-ee2ff
    @yearoldvampire-ee2ff6 жыл бұрын

    Yes

  • @robertg.1162
    @robertg.11626 жыл бұрын

    "40 or so muscles" - euh, how many is it, really? Is the "or so" due to mutations (one more / less in different people) or due to unclear boundaries (where does the fare start and the neck stop etc)?

  • @dotwarner17

    @dotwarner17

    4 жыл бұрын

    A little from column A, a little from column B, plus some facial muscular dexterity, is my guess. Like, I can't really wiggle my ears, so I can't use them to emote, but somebody else might be able to.

  • @alljhfdwtyjbkouvfeyjkhftbn2770
    @alljhfdwtyjbkouvfeyjkhftbn27706 жыл бұрын

    0:48 look at photo number 3 and tell me that that is not ”the father” from far cry 5

  • @Tiffany-dw1ei
    @Tiffany-dw1ei6 жыл бұрын

    Why am I following their expressions again?

  • @kailavogt8512
    @kailavogt85126 жыл бұрын

    Um so inside out really did their research!!!!

  • @waqqas6799
    @waqqas67996 жыл бұрын

    This felt kind of like an art lesson

  • @michaelk5007
    @michaelk50076 жыл бұрын

    Slight difference is with chimps while a smile is okay, showing teeth (even while smiling) is a threat.

  • @heyitzrane3025
    @heyitzrane30254 жыл бұрын

    2:42 Did you mean: *_surprised pikachu face_*

  • @bahestinebun1
    @bahestinebun16 жыл бұрын

    At 4:30 i found a mistake. Bucharest ist the capital city of Romania not Hungary.

  • @onambansal1731

    @onambansal1731

    6 жыл бұрын

    so u think other countries were mentioned with their capitals??. i think they just mean to tell the place and country. nothing related to capitals here

  • @grahamhiscocks1506
    @grahamhiscocks15065 жыл бұрын

    “A kick in the nuts sounds the same in every language” - Abraham Lincoln

  • @chartinguncharted8400
    @chartinguncharted84006 жыл бұрын

    here b4 40!

  • @deanab-se5op
    @deanab-se5op6 жыл бұрын

    👍

  • @tejindersinghswaraj5958
    @tejindersinghswaraj59586 жыл бұрын

    SMILE 😃

  • @kittyykatie
    @kittyykatie3 жыл бұрын

    hmm how can we explain when someone reacts differently? when i am nervous i smile and some ppl have gotten mad at me for smiling in innapropriate situations but i cant help it

  • @loremipsum980

    @loremipsum980

    3 жыл бұрын

    We don't always smile when we're happy, and frown when we're anxious. In fact, our bodies force us to do the opposite when we're experiencing either emotion too strongly to balance them out. Just explain to them you have anxiety or sth. If they don't listen, walk away.

  • @kittyykatie

    @kittyykatie

    2 жыл бұрын

    @@loremipsum980 ahhh so true! thank u i always felt weird when i was smiling when i was scared or sad , thanks

  • @TheOuph
    @TheOuph5 жыл бұрын

    Ekman's methodology was a trainwreck. Completly biaised so he could obtain the conclusions he wanted. His work was critized by PhD and professor Rachael Jack, she is a brilliant scientist with a more modern approach on emotion research. Here's some reading for those interested: scholar.google.ca/citations?user=gO2daQsAAAAJ&hl=en

  • @RustyB5000
    @RustyB50006 жыл бұрын

    yes

  • @bosspree2941
    @bosspree29416 жыл бұрын

    imagine laughing whit out smiling lol

  • @vreascul
    @vreascul6 жыл бұрын

    bucharest is in romania, budapest is in hungary

  • @sophien4125
    @sophien41256 жыл бұрын

    Hi

  • @TarunKumar18
    @TarunKumar186 жыл бұрын

    If we really wish to learn more about universal expressions we should study the facial expressions and behavior of babies whose minds are completely uninfluenced from the outside world

  • @gro2020
    @gro20206 жыл бұрын

    Lmao this reminds of that "disgust face" meme

  • @jaazen4904
    @jaazen49046 жыл бұрын

    don't you ever try to give a like to Justin Y. because HE NEEDS TO REST!!(edit:at least he had his beauty sleep and lookout at the comments,if someone tries to make Justin Y. blow up again,tell me pls)

  • @utkarsh3708

    @utkarsh3708

    6 жыл бұрын

    Tell you what BTW I support him😛

  • @jaazen4904

    @jaazen4904

    6 жыл бұрын

    Dark debunker oh no u

  • @utkarsh3708

    @utkarsh3708

    6 жыл бұрын

    Are you jealous of him ?

  • @SuperOvidiuMihai
    @SuperOvidiuMihai6 жыл бұрын

    For reference see Sonic Adventure 2

  • @jerrij4242
    @jerrij42426 жыл бұрын

    A+

  • @EuDouArteHipHopArtCulture21
    @EuDouArteHipHopArtCulture216 жыл бұрын

    one love : )

  • @ezefauzee
    @ezefauzee6 жыл бұрын

    Was hoping the narrator said Joy instead of Happiness. (since there are Disgust, Fear etc)

  • @lem1332
    @lem13326 жыл бұрын

    I wonder how many Animators were on Ted Ed

  • @artursanti3276
    @artursanti32766 жыл бұрын

    Who else made those face expressions when listed? xd

  • @SirTravelMuffin
    @SirTravelMuffin6 жыл бұрын

    Isn't contemporary research undermining this sort of view? Check out the book "How Emotions are Made." It's a bit lengthy, but it made a very compelling case against the perspective proposed in this video

  • @maddieh1878
    @maddieh18786 жыл бұрын

    There’s a tv show called lie to me on this

  • @ALIAmeer304
    @ALIAmeer3046 жыл бұрын

    Hey.. can I professes my problem. ... I would like to get the knowledge as people get. .. but I can't understand clearly. ... can u please add arabic translation when u up vedios directly? Iam and as much people here are Arabian )

  • @michaelk5007

    @michaelk5007

    6 жыл бұрын

    I'm English, but wish to express my support for your feelings - this is the first time I realize how English the Internet is. Sometimes we need to listen to others to grow in our understanding. Good luck.

  • @kirbymarchbarcena
    @kirbymarchbarcena6 жыл бұрын

    How about the "Poker Faced"?

  • @-TeraBhaiEditz-
    @-TeraBhaiEditz-6 жыл бұрын

    Who who here we heeeee

  • @Krl03
    @Krl035 жыл бұрын

    It makes sense. Communication is very important to a species or else the species will not be as strong. It's biological, like the way a dog automatically wags its tail when it is happy, or bares its teeth when it is being threatened.

  • @kenzaelfellah
    @kenzaelfellah6 жыл бұрын

    4:30 it’s either Bucharest-Romania or Budapest-Hungary. For an educational channel, this sure is a pretty big mess up

  • @predragjovanovic3381

    @predragjovanovic3381

    6 жыл бұрын

    exactly

  • @albertohyeah4355
    @albertohyeah43555 жыл бұрын

    great/

  • @saifullahrahman
    @saifullahrahman6 жыл бұрын

    Ted Ed- quantity and quality