Because you will come to regret it if you don't do it. But we're not going to grade it.

但是我们不会对此计分,因为不计分所以让你们。

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This is great when you want to express regret for something that you perhaps did not do.

当你想表达对一些过去没做成的事情感到后悔时，你可以使用这个句型。

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