They say that you do not need to be extremely intelligent to understand something.

VOA: special.2010.06.27

You need to, if you want something to be printed out inside your code, you need to tell the machine to do that.

你需要，如果你想要,在代码中显示一些东西的话，你需要告诉机器这么做。

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because you've already done it or you don't need to do something because you've already done it before.

因为你之前已经做过，或者你觉得因为之前做过就没有必要再做了。

I've already 课堂 - SpeakingMax英语口语达人

Remember that you can use it to express a need for you to do or have something,

记住，你可以用它来表达你做某事或得到某些东西的需求，

I need 课堂 - SpeakingMax英语口语达人

Or "you need to do something" or "you need not to do something".

或者“你应该做某事”或“你不应该做某事”。

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When you say "I must" what you mean is "I need to do something."

当你说 "I must"的时候，你是指“我必须得做某事。”

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