将胡椒子储藏在密封容器里，当你需要的时候把它磨成粉。

Store the peppercorns in an airtight container and grind the pepper as you need it.

《柯林斯英汉双解大词典》

当你需要穿白马甲的服务员时，他们就在那儿。

The white-jacketed waitstaff are there when you need them.

《柯林斯英汉双解大词典》

我爱你，当你需要拥抱的时候。

I love you when you need hugs.

youdao

However, the thing to remember is, when you look at heats of reaction under those conditions it's all well and good.

相反，需要记住，当你需要知道反应中放出的热量时,这些量是很有用的。

麻省理工公开课 - 热力学与动力学课程节选

But now, when you need more, you can't just say I only want the best bottom land there is.

然而当你需要更多土地时,你不能张口就要这片地区最富饶的土地

耶鲁公开课 - 古希腊历史简介课程节选

So you don't have to be a critic; you have to be strong; but you know what? You can be the average man, because this is a story about the average man.

所以你不需要当一个批评家;,但是你要坚强，知道么？,你可以是平常人,因为这是一个平常人的故事。

耶鲁公开课 - 1945年后的美国小说课程节选