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I have a book.
You have a book.
She, Mary, has a book
He, Tom, has a book.
It, the library, has a book.
They have a book.
Or do you mean the Present Perfect verb HAVE?
I have done my homework.
You have done your homwork.
She has done her homework.
He has done his homework.
It has done its homework.
They have done their homework.
where shall i use have and has 
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