be useful for和be useful to的区别

两者的区别在于前者的介词后面连接的是somebody（人物），后者的介词后面连接的是something（事物）。be useful to在后面加somebody的意思是对…有益；对…有用。be useful for在后面加something的意思是对…有作用；具有…用途。

be useful to造句：This reference book is very useful to our study。这本参考书对我们的学习很有用。We all know trees are very useful to human。我们都知道树对人类很有用。The canal has proved useful to the county in many ways。这条运河在许多方面对这个县很有用。be useful for造句：It is very useful for a person to know how to swim。对一个人来说，学会游泳是非常有用的。The book is useful for making sentences。这本书对造句很有用。I think it would be useful for you to learn the basics of marketing。我认为学习市场营销的基础知识对你很有用。