This is chair/This is a chair.这两句哪一句是错误的?This is chair./This is a chair.这两句哪一句是错误的?两句想表达的意思有什么不同?

This chair is orange.(改成同义句) This is my chair.(改为一般疑问句) is this her chair的同义句 Is this chair[she her hers]? There is no chair in this room.(同义句) Is this your chair?Yes,it's 改错 This is John's chair改成复数句子 this chair is too hard 改为一般疑问句 This is chair/This is a chair.这两句哪一句是错误的?This is chair./This is a chair.这两句哪一句是错误的?两句想表达的意思有什么不同? Is this chair（ ）sale for 15yuan? 改为how引导的感叹句.This chair is very beautful. I spend 50 yuan on this chair.改为同义句. This chair is lighter than that one（中文）This chair is lighter than that one（中文） This is what I This is how I This’s a chair .改错 whoes is this chair?（同义句）（）（）（）this? what is this?______ a chair.A.is thisB.it is C.that is