短语money doesn't grow on trees的字面意思是“钱不会长在树上”，实际想表达的意思是不要乱花钱，因为挣钱不容易。

例句

My daughter Claire wants a car for her 17th birthday, but I can't afford it. Money doesn't grow on trees!

"Mum, can you give me some more pocket money?"

"No I can't - money doesn't grow on trees, you know."

请注意

短语 money is no object 的意思是说你有很多钱，所以钱不是问题。

He lives in a mansion, has three sports cars and goes on holiday every month. Money is no object for him.