But the catch is that the party on the other end of things has to have that same machine or know that same number.

但是那个隐情是对立面的党派,必须有一个同样的机器或者知道那个密钥。

哈佛公开课 - 计算机科学课程节选

I'm really tired and I have a lot of school work to catch up on.

我真是累坏了，我还有许多落下的功课得补起来。

I'd like 实战 - SpeakingMax英语口语达人

So come on up and I'll--okay, But you have to be comfortable on stage, that's the catch 'cause this will be going out on the Internet.

请你们上来，好的，但是，在台上你们必须放松，这是重点，因为这视频会放到网上。

哈佛公开课 - 计算机科学课程节选

I can change everything overnight; it does happen. I put that in for a reason because sometimes some of you have not taken a physics course and you don't know how to do well in physics and slowly you catch on and by the time it's Final exam you crack the code; you know how to do well.

我能一夜之间扭转乾坤,确实有过这样的例子,我这样做是因为,有时你们中有人可能以前没上过物理课,不知道怎样学好物理,但慢慢地你赶了上来,到期末考试的时候,你忽然灵光一闪,考起试来得心应手

耶鲁公开课 - 基础物理课程节选