May: There are so many people that the tickets are all sold out!

人太多了，票都卖完了。

Daniel: Luckily we got the last two.

幸好我们买了最后两张。

May: Look, Danny. The Four Great Inventions!

看，丹单，四大发明！

Daniel: Gunpowder, compass, the paper making, and the printing.

火药、指南针、造纸术和印刷术。

May: I really admire those who made such great inventions!

我真崇拜这些伟大的发明者。

Daniel: May, I don't see why they are great. They are just simple things.

阿美，我不明白有什么伟大的。它们只是些很简单的东西啊。

May: They look simple today. But they were milestones in their times.

它们今天看起来很简单。但在它们那个时代却是里程碑。

Daniel: Milestones? May, you must be kidding.

里程碑？阿美，你在开玩笑吧。

May: Just think Bill Gates, those inventions are as important as the windows system.

想想比尔·盖茨，那些发明的重要性不亚于Windows 操作系统。

Daniel: Well, I suppose the ancient inventors made a lot of money out of them.

我想古代的发明家们肯定从它们身上赚了不少钱吧。

May: No, quite the contrary.

不，恰恰相反。

Daniel: Why? Didn't you say that they were milestones?

为什么？你不是说它们是里程碑吗？

May: Yes, but they went to the public without any patent protection.

是啊，但是它们没有任何专利保护就进入市场了。

Daniel: Well, their inventors were not as clever as Bill Gates.

哦，它们的发明者可没有比尔·盖茨那么聪明啊。

四大发明，指造纸术、指南针、火药和印刷术（也指活字印刷术），是中国古代对世界具有很大影响的四种发明。

这一说法最早由英国汉学家艾约瑟提出并为后来许多中国的历史学家所继承，普遍认为这四种发明对中国古代的政治、经济、文化的发展产生了巨大的推动作用，且这些发明经由各种途径传至西方，对世界文明发展史也产生了很大的影响。