把下面四个句子班委否定句和疑问句：This is my backpack.That is her dictionary.It’s his eraser.

否定句就是在be动词is后加not；疑问句就是将be动词is提到句首.This is not my backpack.Is this my backpack?This is not her dictionary.Is this her dictionary?It's not his eraser.Is it his eraser?当然is not...