系动词与实意动词的区别?

look 后面加形容词,she looks happy.
look 后面加介词：she looks at me.
sound 后面也加形容词：it sounds reasonable.
become 后面加形容词：it becomes easier.
becomes 后面加名词：the man became a doctor.
关键是注意这些词的搭配,这些词差不多都是系动词,也就是说后面不能直接加名词.实意动词后面可以直接加名词.
希望对你有用.