This is a hand复数句快

This is a hand复数句快 This is a book 改为复数句 This is a pear.改为复数句 this is a bus.【变为复数句】 this is a tree 改为复数句 Is this a bus （改为复数句 this is a shirt改为复数句 this is a watch(改为复数句) Is this a book?的复数句 this is a pen.改为复数句 This is a zoo .复数句 This is a shirt .改为复数句 this is a pencil改为复数句 This is a butterfly改为复数句 this is a letter改为复数句 This is a dog :改为复数句 This is my sister 改为复数句快 Is this a plane?yes,it is 改复数句