This is a pen and that is a knife改为复数形式

This is a pen and ____ is a pencil. This is a pencil and a pen还是These are a pencil and a pen This is a pen,and ____is a pencil over there this is a red pen.and that is a green pen.（改为同义句） this is a red pen.and that is a___ ___. this is a my pen This is a nice pen. This is a pen.(this)are pencily This is a pen and that’s an eraser.可不可以写成This is a pen and that is an eraser.呢? This is a pencil and a pen还是This are a pencil and a pen,二楼说的也许对，但我只问用IS还是ARE This is a pen and that is a knife改为复数形式 This a pen.that is a pen,什么 This is a pen.就划线提问 this is a pen.改为复数句 this is a pen改成一般疑问句 This is a pen.改为一般疑问句 is this a youe pen 怎样改错 This is a nice pen.的问句 This is a pen.(改为复数形式)