Are the books on the bookcase?(作否定回答）

Are the books on the bookcase?(作否定回答） are these books on the bookcase?作否定回答 Are the books in the bookcase?(作肯定回答) Are the books on the desk? 作否定回答 the books are in the bookcase.(改为否定句） Are the books in the backpack?（作否定回答） The books are in the bookcase.变为否定句 The books are in the bookcase(改为否定句) His books are in the bookcase.改为否定句 "Ten books are in the bookcase"改为否定句是什么 There are some books on the desk.(改为一般疑问句,并作否定回答) Her books are on the sofa变一般疑问句并作否定回答