This is a box.(改为复数句）是These are boxes.还是These are many boxes.

This is a box.改为复数形式 this is a box改为复数 This is a box and that is a knife （改为复数句） __what is it _IT is a box改为复数句 Is's a pencil-box.改为复数句 It is a large box.(改为复数句） what isit?lt is a box改为复数句 This is a book 改为复数句 This is a pear.改为复数句 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) this is a pen.改为复数句 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