他们必须能够在你需要他们的时候做出回应。

They have to be able to respond when you want them.

youdao

所以我需要在你来的时候把它送过去。

So I would need to deliver it at a time when you're in.

youdao

你可以预先调好暖气，使它在你需要的时候启动。

You can preset the radiators to come on when you need them to.

《牛津词典》

You handle them very special in terms of being extra careful in a very high ventilation area, in hoods is how you handle them.

在使用它们的时候你需要格外小心,必须在通风条件非常好的地方，在通风柜中才行。

麻省理工公开课 - 化学原理课程节选

There are some simple things that you should always look at when you're looking for bugs.

当你在找错误的时候,需要注意几件简单的事。

麻省理工公开课 - 计算机科学及编程导论课程节选

One more issue is, you have another decision when you run up to hit this, hit the penalty other than just left and right.

另一个问题是,在你主罚点球的时候,除了左路右路外还有别的需要考虑吗

耶鲁公开课 - 博弈论课程节选