这句话的问句有3种呢，要看提问的部分是哪里
如果划线部分是It，答案：What's on the chair?
如果划线部分是on the chair，答案：Where is it?
如果只是一般疑问句的提问，答案：Is it on the chair?
如有疑问，欢迎追问哦~~
Where is it?
Where is it? 它在哪里？It's on the chair. 它在椅子上。
