it is an old backpack的复数形式

网友回答

these are old backpacks
======以下答案可供参考======
供参考答案1:
they are old backpacks
供参考答案2:
They are old backpacks.
供参考答案3:
These are old backpacks.
供参考答案4:
应该是：They are old backpacks。