cut one's coat according to one's cloth，直译是“看布裁衣”，真实含义是量力而为；适应环境；量体裁衣。

【例句】
We can't afford such a big house, we have to cut our coat according to our cloth.
我们买不起这么大的房子，我们得量力而为。

Now that you have a child to feed,　you must cut your coat according to your cloth and practise economy.
你现在要养育一个孩子，必须量入为出节省开支了。