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。

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If you don't know what you want, you might end up getting something you don't want.

如果你不知道自己想要什么，你可能会到头来得到自己不想要的东西。

《柯林斯英汉双解大词典》

You must see yourself clearly, and know what you want to get.

你必须看清自己，知道自己想要什么。

youdao

We want to know what you have to say about the effects of the Internet on language and writing.

VOA: special.2010.01.28

And Joe Jackson had this song which had the lyric, like, you can't get what you want unless you know what you want.

杰克森有句歌词这么写的,汝欲求之,必先知之

耶鲁公开课 - 博弈论课程节选

So like, when you're going to Chinatown, it's good to know what you want to buy.

所以，如果你要去唐人街，你还是知道自己想买什么的好。

强烈推荐购物 - SpeakingMax英语口语达人

You know what you want, but you're not always sure where to get it.

CNN: WINDOWS SHOPPING

"I know what you want to ask and I will try hard not to answer you, " he told BBC Scotland when quizzed.

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Let your colleague or employee know what you want to talk about.

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