You have to know what's what and when to draw the line.

你必须搞清状况以及自己的底线。

柯林斯例句

Maybe he doesn't look very clever , but he knows what's what.

别看他傻呵呵的, 心里可有数.

《现代汉英综合大词典》

He'll show you what's what in time.

到时候他会把事实真相告诉你的.

《现代汉英综合大词典》

You should come across the river with us. Then you will really see what's what.

你应该和我们一起过河，那时你就会了解实情了。

柯林斯例句

With so many things mixed up, it's hard to make out what's what.

许多问题绞在一起, 闹不清楚.

《现代汉英综合大词典》

You've old and pigheaded. You don't know what's what.

你真被迷了,老昏了,一点也不会想了.

汉英文学 - 中国现代小说

I guess I'm your auntie and I know what's what.

不管怎么说,我总是你的姑妈,也不是不明事理.

飘（部分）

You're old enough now to know what's what.

你已经不小了,应该知道好歹了.

辞典例句

There are also other should pay attention to what's what?

此外还有什么其他要注意的 么 ?

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I keep my ears open and I what's what around the office.

我一直在注意听,知道办公室发生的情况.

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When it comes to pedagogical psychology, the young scholar knows what's what.

讲起教育心理学, 这位年轻的学者是很在行的.

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In the choice you need to know what's what.

在选择上也需要您心里有数.

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I beg you to tell me what's what.

我恳求你告诉我事情的真相.

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He's very clear and knows what's what.

他很聪明,懂得是非曲直.

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But what's what about book publishers and writers.

但是图书发行商和作者又怎么样?

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