Suppose you want to train somebody to do something and you want the training such that they'll keep on doing it even if you're not training them anymore, which is typically what you want.

假设你想训练某人做某事,你想要找到一种训练方法,使得他们即便不再接受训练,也依然能够持续展现某种行为，而这正是你想要的。

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You can use "Do you" when you want to find out if somebody wants to do something,

你可以用“Do you”来了解其他人想做什么，

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You can say "Why don't you" when you want to suggest that somebody else do something.

当你想建议他人做某事时，你可以说“Why don't you~?”。

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