think of意为“考虑到、想到”,后常接代词、名词或动词-ing形式；意为“认为”时,一般用于疑问句中,与what连用.如：
It's good to think of the future．考虑到未来是对的.
He thought of a good plan．他想到一项好计划.
What do you think of the play?（＝How do you find ／like ／enjoy the play?）你觉得这部戏剧怎么样?
think about可接名词、动词-ing形式或由疑问词引导的不定式或宾语从句,表示“考虑……”.如：
He's thinking about a problem．He has thought about it for a long time．他正在考虑一个问题,他已经考虑了很长时间了.
Please think about how to tell her the bad news．请考虑一下,如何把这个不幸的消息告诉她.
He carefully thought about what I said．他仔细考虑了一下我所说的话.
think over意为“仔细考虑”,后接名词或代词作宾语.当后接代词时,应把代词放在over之前.如：
Let me think it over．让我好好想一想.
Please think over what I have said．请仔细考虑我说的话.