Today, all countries are involved in, and to varying degrees dependent on, trade with other countries. 29 international trade, nations would be limited to the goods and services produced within their own borders.
答案：(C) Without
假設語氣的語境（配合would be），「沒有國際貿易，各國將僅限於自己國內生產的商品和服務」，Without（沒有）符合這種假設條件；Despite（儘管）、Between（在……之間）、Under（在……之下）都不合。
Despite（儘管）和 Without（沒有）在中文裡都帶點「不管有沒有」的味道，考試時很容易混；而且 Despite 是比較晚才學到的字，看起來比較「高級」，反而容易被挑走。
決定性的線索是主要子句裡的 would：nations would be limited to the goods and services produced within their own borders（各國將只能侷限於自己境內生產的商品與服務）。劍橋 English Grammar Today 的「Would」條說明，would 用在條件句的主要子句，談的是想像出來的情況。既然是想像，前面就必須有一個「假設的條件」。without 加名詞正好可以當條件用，等於一個 if 子句 — 劍橋 English Grammar Today 的「Without」條指出，without 帶有否定意味，without 加 V-ing 可以表達「如果某人不做某事」。還原成 if 子句驗算：Without international trade, nations would be limited to… ＝ If there were no international trade, nations would be limited to…（如果沒有國際貿易，各國就只能侷限於……）再把 Despite 代進去讀完整句：Despite international trade, nations would be limited to…（儘管有國際貿易，各國仍會被侷限於……）— 這和全文主旨完全相反，文章從頭到尾都在說貿易讓各國突破自身國境的限制。「代進去把整句讀完」永遠比只看單字中譯安全。這個句型你在道謝時早就用過：Without your help, I couldn't have finished it.（沒有你的幫忙，我不可能完成。）
Despite（儘管）表讓步，後面接名詞，例 despite the rain（儘管下雨），與 would 的假設語意搭不起來。Between（在……之間）後面通常接兩者，或接 A and B。Under（在……之下；在……情況下）例 under pressure（在壓力下），但 under international trade 不是英文的說法。
Without + 名詞（若沒有……）、without（沒有；如果沒有）、despite + 名詞（儘管……）、in spite of + 名詞（儘管……）、be limited to（僅限於、侷限於）、within one's borders（在國境之內）、be dependent on（依賴……）。
International trade is the exchange of goods and services between countries. Trade is driven by different production costs in different countries, making 26 cheaper for some countries to import goods rather than make them. A country is said to have a comparative advantage over another when it can produce a commodity more cheaply. This comparative advantage is 27 by key factors of production such as land, capital, and labor.
While international trade has long been conducted in history, its economic, social, and political importance has been 28 in recent centuries. During the 1990s, international trade grew by nearly 8.6 each year. In the year 1990 alone, the growth in trade in services was as high as 19. Today, all countries are involved in, and to varying degrees dependent on, trade with other countries.
29 international trade, nations would be limited to the goods and services produced within their own borders. Trade is certainly a main 30 force for globalization. It is also the subject of many international agreements that aim to govern and facilitate international trade, such as those negotiated through the World Trade Organization (WTO).