把下面的句子改为一般疑问句 并作肯定或否定回答 I an in Class FIve,GRade Seven They are in Class ELe

are you in class five,grade seven?
yes,i am.no,i am not.
are they in class eleven?
yes,they are.no,they aren't.
is he twelve years old?
yes,he is.no,he isn't.