Is's a pencil-box.改为复数句
Is's a pencil-box.改为复数句
Is's a pencil-box.改为复数句
Is's a pencil-box.改为复数句
These are pencil boxes.
There are some pencil boxes
Is's a pencil-box.改为复数句
Is's a pencil-box.改为复数句
Is's a pencil-box.改为复数句
These are pencil boxes.
There are some pencil boxes