It is not my book.（缩写句子） Is that a key?（做肯定回答）
问题描述：
It is not my book.（缩写句子） Is that a key?（做肯定回答）
It is my mother's watch.（改为一般疑问句,并作否定回答）
----（ ）（ ）（ ）mother's watch?
----( ）,（ ） （ ）.
答
It isn't my book.
Yes,it is.
Is this your mother's watch?
--No,it isn't.