it is anold backpack的复数形式

it is anold backpack的复数形式 It is my backpack _your backpack It is in the backpack? It is in the backpack? ________________?(your,backpack) yes,it is . It is his backpack改否定句 Not ,is ,my,it,backpack(連詞成句) it is my backpack(改为否定句) it（ ）my backpack. Is the backpack on the floor No,it is 改错 the backpack is empty .there is n________ in it. not,is,my,it,backpack 连词成句 not、 is、 his、 backpack、 it连词成句 it is an old backpack的复数形式 Is it in the backpack?做否定回答 Is it in the backpack?（给出否定答语） Is ____ your backpack No,it isn't .My backpack is big.That one is small.填this还是that Your backpack is where is backpack