跟讀練習: Specialization and Trade: Crash Course Economics #2 - 通過影片學習英語口語
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1
Adriene Hill: Hi I'm Adriene Hill. Mr. Clifford: And I'm Mr. Clifford.
阿德里安娜·希爾：大家好，我是阿德里安娜·希爾。克利福德老師：我是克利福德老師。
2
Welcome to Crash Course Economics.
歡迎收看《Crash Course 經濟學》。
3
Adriene: Here at Crash Course, we recognize that difficult subjects are sometimes fraught with truly unintelligible vocabulary that's difficult for us regular people to understand.
阿德里安娜：在Crash Course，我們意識到有些複雜的學科往往充斥著普通人難以理解的、完全晦澀難懂的專業術語。
4
Mr. Clifford: But it doesn't have to be that complicated. Remember, economics is the study of scarcity and choices. We have limited resources, so we need a way to analyze the best way to use them. We need economics to make wise decisions in the future, but it also helps us understand the past.
克利福德先生：但事情其實不必這麼複雜。記住，經濟學是研究稀缺性與選擇的學科。我們的資源有限，因此需要一種方法來分析利用這些資源的最佳方式。我們需要經濟學來在未來做出明智的決策，同時它也能幫助我們理解過去。
5
Adriene: Most empires, wars, and human endeavors can be explained using economics. All you have to understand is who wanted what. The American Civil War wasn't just about freedom, it was fought because southern states wanted to keep using cheap slave labor. It was economics.
阿德里安娜：大多數帝國的興衰、戰爭的爆發以及人類的各種活動都可以用經濟學來解釋。你只需要弄清楚誰想要什麼。美國內戰不僅僅是為了自由，它的爆發是因為南方各州想要繼續使用廉價的奴隸勞動力。這就是經濟學。
6
Mr. Clifford: Econ can explain so much about the world, and that's why we love teaching it, and that's what makes it the greatest subjects of all time.
克利福德先生：經濟學可以解釋世界上的很多事情，這就是為什麼我們喜歡教授這門學科，也是它成為有史以來最棒的學科的原因。
7
Adriene: Take that physics! We're comin' for ya!
阿德里恩：物理學，接招吧！我們來找你算賬了！
8
Adriene: Let's stick with this history theme and talk about the progress of humanity throughout the ages. Using measurements like life expectancy, child mortality, and income per capita, we can show the majority of humans that ever lived had terrible lives. Statistically speaking.
阿德里安娜：讓我們繼續圍繞這個歷史主題，談談人類各個時代的發展程序。通過預期壽命、兒童死亡率和人均收入等指標，我們可以證明，從統計資料來看，有史以來大多數人類的生活都非常糟糕。
9
It wasn't until the industrial revolution that people saw significant and sustained increase in their standard of living. Populations skyrocketed, but so did life expectancy and food supplies and hospitals and eventually toilets and refrigerators.
直到工業革命時期，人們的生活水平才出現了顯著且持續的提升。人口數量急劇增長，但預期壽命、糧食供應、醫院數量也隨之增加，後來又出現了廁所和冰箱。
10
Mr. Clifford: It was at the beginning of the industrial revolution that Adam Smith, the first modern economist, wrote his book An Inquiry Into the Nature and Causes of the Wealth of Nations or AIITNACOTWON. He wasn't great at naming books, but he was really good at explaining the source of prosperity. Smith concluded it was specialization, or what he called the division of labor, that made countries wealthy. Let's go to the Thought Bubble.
克利福德先生：工業革命初期，第一位現代經濟學家亞當·斯密撰寫了《國民財富的性質和原因的研究》，簡稱AIITNACOTWON。他不太擅長給書起名字，但非常擅長解釋繁榮的根源。斯密的結論是，專業化，也就是他所說的勞動分工，才是國家富裕的原因。我們進入「Thought Bubble」環節。
11
Adriene: When I think of specialization, I think of a pizza restaurant where different workers have specific tasks like preparing the ingredients, making the pizza, putting it in the oven, taking it out and putting it in the box. This division of labor makes each worker more productive since they can each focus on the thing they do best, and they don't waste time switching between jobs.
阿德里安娜：一提到專業化，我就會想到披薩店，店裡不同的員工有各自明確的分工，比如準備食材、製作披薩、把披薩放進烤箱、烤好後取出來裝進盒子裡。這種勞動分工能讓每個員工的工作效率更高，因為他們可以專注於自己最擅長的事，也不會浪費時間在不同工作之間切換。
12
But specialization goes beyond the assembly line for pizza. To produce the cheese, there was a dairy farmer who specialized in raising cows; the oven was designed and manufactured by people who specialize in engineering ovens; the friendly moustache guy on the pizza box?
但專業化分工遠不止披薩的生產線。製作乳酪需要有專門飼養奶牛的奶農；烤爐是由專門設計製造烤爐的工程師研發生產的；披薩盒上那個留著鬍子的友善大叔呢？
13
Someone had to stamp him on there. I love that guy!
總得有人把他印在上面啊。我太愛這傢伙了！
14
Adam Smith observed, "in every improved society, the farmer is generally nothing but a farmer; the manufacturer, nothing but a manufacturer. The labour... necessary to produce any one complete manufacture, is almost always divided among a great number of hands." Imagine what it would be like to make a pizza completely on your own. From scratch. You would have to grow the wheat and tomatoes and raise the cow, you'd make the flour, the cheese, the oven, the pan, and then draw the moustache guy on the box. Without specialization, if you want something, you have to make it yourself.
亞當·斯密曾指出：“在所有進步的社會裡，農民通常就只是農民，工匠就只是工匠。生產一件完整製成品所需的勞動……幾乎總是由大量不同的人手分工完成的。”試想一下完全靠自己從頭開始做一份披薩會是什麼樣子。你得自己種小麥、種番茄、養奶牛，自己做麵粉、做乳酪、造烤爐、做烤盤，還要在披薩盒上畫那個留鬍子的小人。沒有專業化分工的話，你想要什麼東西，就必須自己動手做。
15
And for thousands of years of human history, specialization was, well, pretty minimal.
在人類歷史的數千年裡，專業化程度其實一直都相當低。
16
Of course humans specialized prior to the industrial revolution, it's one of the marks of civilization that we mentioned in our World History series, but the modern era has taken this to the extreme. Think of how many people from how many different specialized fields it takes to make a smartphone, all of them working in harmony so I can tweet my super profound thoughts.
當然，在工業革命之前人類就已經有了專業化分工，這也是我們在《世界歷史》系列中提到的文明標誌之一，但現代社會將這種分工推向了極致。想想製造一部智慧手機需要多少來自不同專業領域的人，他們所有人協同合作，才能讓我在推特上釋出那些極其深刻的想法。
17
Thanks Thought Bubble! So specialization makes people more productive, but Adam Smith said that it's trade that makes them better off. Assume that John can produce either pizza or t-shirts. If he's way better at making pizza, then he should specialize in making pizza and then trade with someone else like Hank who's way better at making t-shirts.
感謝Thought Bubble！專業化能提高人們的生產效率，但亞當·斯密指出，真正讓人們生活變得更好的是貿易。假設約翰既能生產披薩，也能製作T恤。如果他做披薩的能力遠強於製作T恤，那他就應該專門生產披薩，然後和漢克這樣更擅長製作T恤的人進行交易。
18
Everyone knows Hank's better at making t-shirts, right? With trade, each of them can end up with more pizza and shirts than if they tried to make them on their own.
大家都知道漢克更擅長製作T恤，對吧？通過貿易，他們每個人最終能得到的披薩和T恤都會比自己獨自生產時更多。
19
To fully explain this idea of the benefits of trade, we need to show you an economic model, but before we go any further, know that economists geek out over models and graphs.
為了全面解釋貿易好處這一理念，我們需要向你展示一個經濟學模型，但在進一步講解之前，要知道經濟學家們對模型和圖表可是非常熱衷的。
20
Don't get all worked up about the numbers; they're not that complicated. Models are just visuals to help us simplify and explain concepts. It's time for the model! So let's go to the runway.
別對這些數字太緊張了，它們沒那麼複雜。模型只是幫助我們簡化和解釋概念的視覺化工具。現在該輪到模型登場了，讓我們走上展示臺吧。
21
Mr. Clifford: Now this is the first graph you'll see in an economics textbook. It's called the production possibilities frontier, or PPF. The PPF shows the different combinations of two goods being produced using all resources efficiently.
克利福德先生：現在這是你會在經濟學教科書裡看到的第一張圖。它被稱為生產可能性邊界，簡稱PPF。PPF展示了在有效利用所有資源的情況下，兩種商品產出的不同組合。
22
Now here's a made up example. If the United States uses all of its workers and factories to produce airplanes, it can produce 500 per day, but they can't produce any shoes. Now if they use all their resources to produce shoes, they can produce 1000 tons per day, but they can't produce any planes.
現在舉一個虛構的例子。如果美國投入所有勞動力和工廠來生產飛機，每天可以生產500架，但無法生產任何鞋子。如果他們把所有資源都用來生產鞋子，每天可以生產1000噸鞋子，但無法生產任何飛機。
23
Now because the United States has limited resources, they can't produce any combination beyond the production possibilities frontier, so it's impossible to produce 500 planes and 1000 tons of shoes.
現在，由於美國的資源有限，他們無法生產超出生產可能性邊界的任何組合，因此生產500架飛機和1000噸鞋子是不可能的。
24
Adriene: Wait wait wait, Mr. Clifford, I want to stop you here for a second. We don't live in a world where there are only two things that a country can produce. There are like a million things that US workers can choose to make: toilet paper, zippers, adorable stuffed kitty cats holding hearts, artisanal sauerkraut -- we don't live in a world of just shoes and airplanes, so what's the real world value of the production possibilities frontier?
阿德里安娜：等等，克利福德先生，我想在這裡打斷您一下。我們生活的世界裡，一個國家能生產的東西可不止兩種。美國工人可以選擇生產的東西有成千上萬種：衛生紙、拉鏈、抱著愛心的可愛毛絨小貓、手工酸菜——我們可不是生活在一個只有鞋子和飛機的世界裡，那生產可能性邊界在現實世界裡的價值到底是什麼呢？
25
Mr. Clifford: The idea is once you really understand that there's trade-offs between producing two goods, that same logic applies for any number of goods. Adding additional goods makes it more complex but doesn't really add any more insights, so economists usually just stick with two goods.
克利福德先生：核心觀點是，一旦你真正理解生產兩種商品之間存在權衡取捨，這一邏輯同樣適用於任意數量的商品。增加更多商品會讓情況變得更復雜，但並不會帶來更多新的洞見，因此經濟學家通常只研究兩種商品的情況。
26
Now, what if American companies mismanage their resources and try to produce planes in shoe factories and shoes in plane factories? Well, they'd be at a point inside the production possibilities frontier, showing an inefficient use of resources. So every possible combination inside the curve is inefficient, and on the curve is efficient and outside the curve is impossible.
那麼，如果美國企業管理不善，試圖在鞋廠生產飛機、在飛機制造廠生產鞋子，會發生什麼呢？它們就會處於生產可能性邊界以內的某個點，這代表著資源的低效利用。因此，曲線內部的所有組合都是低效的，曲線上的組合是高效的，而曲線外部的組合是無法實現的。
27
Now let's compare this PPF to China's. China can produce 100 planes per day or 800 tons of shoes. Since the United States can produce more planes than China, they have an absolute advantage in the production of planes. The US also has an absolute advantage in the production of shoes.
現在我們將這條生產可能性邊界與中國的進行比較。中國每天可以生產100架飛機或800噸鞋子。由於美國能生產的飛機數量多於中國，因此美國在飛機生產上具有絕對優勢。美國在鞋子生產上同樣具有絕對優勢。
28
Since the US can produce more of both goods, you might think there's no reason to trade, that they should just produce both on their own. Well, no. Remember, specialization and trade makes people, and in this case countries, better off.
既然美國能夠生產這兩種商品，你可能會認為沒有必要進行貿易，他們自己生產這兩種商品就好了。但事實並非如此。請記住，專業化生產和貿易能讓人們受益，在這個例子裡，是讓各個國家受益。
29
Now stick with me, let's calculate the opportunity cost for the United States to produce one plane. Every single time they produce an additional plane, it costs them two tons of shoes. China on the other hand gives up 8 tons of shoes for each plane they produce, and since the US has a lower opportunity cost, they have what's called a comparative advantage. China has a comparative advantage in the production of shoes.
現在請繼續跟著我，我們來計算美國生產一架飛機的機會成本。每當他們多生產一架飛機，就要付出兩噸鞋子的代價。而中國每生產一架飛機則要放棄八噸鞋子，由於美國的機會成本更低，他們就擁有了所謂的比較優勢。中國在鞋子生產上具有比較優勢。
30
But here's the best part, if the US specializes in planes, they can import shoes from China at a lower opportunity cost than if they produce shoes themselves. For example if these two countries make a deal to trade one plane for four tons of shoes, The US would be better off.
但最妙的是，如果美國專門生產飛機，他們從中國進口鞋子的機會成本會比自己生產鞋子更低。舉個例子，如果這兩個國家達成協議，用一架飛機交換四噸鞋子，那麼美國的境況會更好。
31
They would rather get four tons of shoes per plane from China than only get two tons per plane by making shoes on their own. Now, China is also better off. They would rather trade four tons of shoes for a plane than give up 8 tons for producing a plane on their own.
他們寧願每架飛機從中國獲得四噸鞋子，也不願自己生產鞋子，每架飛機只能運兩噸。現在中國的境況也更好了。中國寧願用四噸鞋子換一架飛機，也不願為了自己生產一架飛機而付出八噸鞋子的代價。
32
Now hopefully your head isn't spinning. Being able to do these calculations is good, but it's more important to understand the main idea. Individual and countries should specialize in producing things in which they have a comparative advantage and then trade with other countries that specialize in something else. This trade is mutually beneficial.
希望現在你還沒有被繞暈。能夠進行這些計算固然很好，但更重要的是理解核心思想。個人和國家都應該專門生產自己具有比較優勢的產品，然後與專門生產其他產品的國家進行貿易。這種貿易是互利的。
33
Now that's the production possibilities frontier. In the real world, it's way more complicated than this simplified model, and we're only in the beginning.
這就是生產可能性邊界。在現實世界中，情況比這個簡化模型要複雜得多，而我們才剛剛開始探討。
34
Adriene: So this graph is super simplified, but the idea that countries should focus on producing the products for which they are better suited is huge. Way huge.
阿德里安娜：這張圖表雖然非常簡化，但各國應專注於生產自身更具優勢的產品這一理念至關重要，極其重要。
35
In reality, the US is the world's leading manufacturer and exporter of airplanes. It produces more than 40% of all planes. At the same time, the US produces less than 2% of the world's shoes, electing instead to import them from countries in Asia. The graphs aren't real, but the concepts are.
實際上，美國是全球領先的飛機制造國和出口國，其產量佔全球飛機總產量的40%以上。與此同時，美國生產的鞋類不足全球的2%，而是選擇從亞洲國家進口。這些圖表並非真實資料，但所呈現的概念是成立的。
36
Another reason you should learn this is because you might hear a politician or someone on the news argue that international trade destroys domestic jobs, and even though it may seem counterintuitive, economists for centuries have argued that trade is mutually beneficial to whoever's trading. Now you know why.
另一個你應該學習這個知識點的原因是，你可能會聽到政客或新聞裡的人聲稱國際貿易會摧毀國內就業，儘管這聽起來可能有悖直覺，但幾個世紀以來經濟學家一直認為貿易對所有參與方都是互利的。現在你就明白原因了。
37
Now to be fair, there are all sorts of other intolerable issues associated with international trade, like child labor, dangerous working conditions and pollution, and we promise to address these in a future video. But if there's one point on which most economists agree, it's that specialization and trade makes the world better off.
公平地說，國際貿易還伴隨著各種其他難以容忍的問題，比如童工、危險的工作環境和汙染，我們承諾會在未來的影片中討論這些問題。但如果說大多數經濟學家有一個共識，那就是專業化分工和貿易能讓世界變得更好。
38
No country in recent decades has achieved sustained improvements in living standards without open trade with the rest of the world. Countries like Cuba, Venezuela, Zimbabwe, and Iran that are voluntarily or involuntarily cut off from the world remain less economically developed than they could be.
近幾十年來，沒有任何一個國家在不與世界其他地區開展開放貿易的情況下實現生活水平的持續提升。那些主動或被動與世界隔絕的國家，如古巴、委內瑞拉、辛巴威和伊朗，其經濟發展水平始終未能達到本可達到的高度。
39
On the other hand, countries that have opened their doors to trade like Japan and Taiwan, or, more recently, China and India, have seen massive improvements in their standards of living.
另一方面，日本、臺灣，以及近年來的中國和印度這些開放貿易的國家和地區，其生活水平都得到了大幅提升。
40
Mr. Clifford: Adam Smith was on to something. Self-sufficiency is inefficiency and inefficiency can lead to poverty.
克利福德先生：亞當·斯密說得有道理。自給自足就是低效率，而低效率會導致貧困。
41
Adriene: Next time we'll show you how some of these ideas get turned into economic systems and how these systems contribute to the differences between countries.
阿德里安娜：下一期我們會向大家展示這些理念是如何轉化為經濟體系的，以及這些體系如何造成各國之間的差異。
42
Thanks so much for watching, we'll see you next week.
非常感謝大家的觀看，我們下週再見。
43
Crash Course is made with the help of all these nice people who've explored the far reaches of the production possibilities frontier to bring you this show. If you want to keep Crash Course for everyone forever, please consider subscribing over at Patreon. Patreon is a voluntary subscription service that allows you to pay whatever you want monthly and make Crash Course exist. Thanks for watching. Don't forget to be irrationally exuberant.
Crash Course 是在所有這些優秀人員的協助下製作完成的，他們竭盡所能拓展生產可能性邊界的極限，只為給大家帶來這檔節目。如果您希望 Crash Course 能永遠為所有人提供，請考慮在 Patreon 上訂閱支援。Patreon 是一個自願訂閱平臺，您可以每月支付任意金額，支撐 Crash Course 的持續運營。感謝觀看，別忘了保持那份非理性的熱情與活力。
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背景與上下文
在這段對話中，Adriene Hill 和 Mr. Clifford 討論了經濟學的基本概念，特別是專門化和貿易的重要性。他們指出，經濟學並不是難以理解的學科，反而是生活中無處不在的選擇和資源的合理分配。通過歷史的視角，展示了經濟如何影響人類社會的發展和繁榮。他們提到，專門化可以提高生產力，而貿易則是讓不同領域的生產者能夠共享資源，以達到雙贏的效果。
日常交流中的五個常用短語
- 經濟學是研究稀缺和選擇的學科。 (Economics is the study of scarcity and choices.)
- 專門化可以提高生產力。 (Specialization can increase productivity.)
- 貿易使人們更富裕。 (Trade makes people better off.)
- 資源的有效利用是關鍵。 (Efficient use of resources is key.)
- 比較優勢是理解貿易的基礎。 (Comparative advantage is the basis for understanding trade.)
逐步跟讀指南
要有效提升你的英語口語能力，尤其是在經濟學這樣複雜的主題上，以下是逐步跟讀的指導：
- 選擇適當的片段： 從影片中選取1-2分鐘的內容，確保這個部分包含較為清晰的對話和解說。
- 播放原聲： 首先只聽一次，讓自己理解內容大致意思。在此過程中，可以嘗試用自己的話重複或總結。
- 逐句跟讀： 暫停影片，反覆播放每一句話，並儘量模仿發音和語調。這是進行英語影子跟讀的關鍵部分。
- 對比反思： 完成跟讀後，回過頭去再聽原聲，注意自己在發音和語調上的不足，並加以改進。
- 整合練習： 最後，嘗試用影片中的短語進行造句，模擬日常交流場景，例如在雅思口語練習中使用它們。
通過這種“影子跟讀” (“shadow speak”) 方法，你將能夠更有效地利用“看 YouTube 學英語” 的資源，提升自己的英語能力。將自己置於真實的對話中，專注於語速和發音，能極大地提高你的語言自信心。這將幫助你在實際交流中更流利、更自然地表達自己。
影片中的語法
說話人最常用的結構，並附上影片中的原話：
| 結構 | 影片中的用法 |
|---|---|
| 現在完成時 have/has + 過去分詞 — 過去發生但與現在仍有關聯的事 | has taken · have argued · has achieved |
| 被動語態 be + 過去分詞 — 強調發生了什麼，而不是誰做的 | can be explained · was designed · being produced |
什麼是跟讀法？
跟讀法 (Shadowing) 是一種有科學依據的語言學習技巧，最初開發用於專業口譯員的培訓，並由多語言者Alexander Arguelles博士普及。這個方法簡單而強大：您在聽英語母語原聲的同時立即大聲重複——就像是一個延遲1-2秒緊跟說話者的影子。與被動聽力或語法練習不同，跟讀法強迫您的大腦和口腔肌肉同時處理並模模擬實的講話模式。研究表明它能顯著提高發音準確性，語調，節奏，連讀，聽力理解和口語流利度——使其成為雅思口語備考和真實英語交流最有效的方法之一。