ask for the moon 异想 天开

You might as well ask for the moon as for a bicycle.

你要辆自行车就像要天上的月亮一样。

Don't ask for the moon, Mr. Jones.Be reasonable, please.

别异想天开了，琼斯先生。请理智点儿吧。

Oh, Jerry, let's not ask for the moon. We have the stars.

噢，杰瑞，不要再祈求得到月亮了，我们已经拥有星星了。

　reasonable['riːznəbl]adj.讲理的，明事理的

ask for trouble/it 自讨 苦吃

Driving after drinking alcohol is asking for trouble.

酒后开车是自讨苦吃。

Don't ask for trouble by worrying about exams.

别为考试担心而自寻烦恼了。

You'd better not ask for it.

你最好不要自讨苦吃。