If you must move, don't follow a stream unless you know it, and in that case, you are not lost.

如果你非要走动的话，别顺着溪流走，除非你对它很熟悉。但是如果你很熟悉，那你就不会迷路了。

youdao

Keeping things short and sweet not only shows people that you are concise and don't waffle, but that you also know what you want.

亲切简洁的语言不仅彰显了你简明的个性，不会被误认为是在胡扯，还让对方知道你是一个知道自己想要什么的人。

youdao

You have come to Frankfurt to stay with me, don't you know that?

你来法兰克福是为了和我住在一起，这你不知道吗？

youdao

You know, it's like three dollars for something that's, I don't know, in my mind pretty luxurious."

VOA: special.2010.04.12

If you don't know why you're about to eat cake like that you will soon, but you know this.

如果你现在还不知道为什么将要吃到那样的蛋糕,很快就会知道的，你清楚这一点。

哈佛公开课 - 计算机科学课程节选

Or perhaps, you could be trying to explain that you don't know whether you can do something or not by a certain date.

又或者，你正在试图解释你没法确定你是否能在一个指定日期前做完某件事。

I don't know 课堂 - SpeakingMax英语口语达人

You just--if you're a military man, you know that you just don't do these sorts of things because once you give just the slightest bit of leeway, there are those in the armed forces who will take advantage of that.

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So you should be wise enough to know that if you don't explain what you are doing, people will mistrust you.

FORBES: Dow Jones Interactive

If you don't know the players and you don't the people that you're dealing with, then you're not going to solve the crime.

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