把窗户关好，不然屋子里就太冷了。

Shut the window, otherwise it'll get too cold in here.

《牛津词典》

在你离开之前，要注意把窗户关好。

See that the Windows are closed before you leave.

youdao

把窗户关好，以防下雨。

Keep the window closed in case it rains.

youdao

And now let's suppose that your parents are going away for the weekend and they leave you with the following instructions: If it's raining tomorrow morning, when you wake up, you are to close the windows, open the door and let the cat in, phone the grocer and have him send over the following list of groceries. All right.

现在假设你们的父母这周末,离开了，给你们留下了,以下的一些指示：,如果明天早上下雨了，醒来的时候，要把窗户关好，打开门,让猫进来，打电话给杂货店并且让他,送来以下的生活用品，好的。

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