Today,I go to a book store with my classmate.In order to buy two books that can enjoy it together and share it each other.So I want to buy an English book talk about science,and he wants to buy an English book talk about galaxy.I say my science book is better than you,he says his galaxy book is better than mine.Suddenlym we find another book is talking about universal,then we say it is the best book that we want!Finally,we are happy to buy three books.