is this a pen ___ your pencil case

This is a pen.对划线部分提问 ___ ___? is this a pen ___ your pencil case A:that's your pen.___ is my pen B:Do you __ this is interesting? What's this?——___.(①It's a pen.②This is pen.③This is an pen.④It's a pen.) 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___ ___. Is this your pen?Yes,___(thank). this is a my pen This is a nice pen. This is a pen.(this)are pencily This a pen.that is a pen,什么 IS this his pen?YES,__ ___.it's____. 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)