题目内容：

they are their computer.单数 this is my watch.复数 whose teacher are these?they are ours.单数
ls this your pencil?yes,it is.复数

优质解答

It is their computer.
These are our watches.
Whose teacher is he/she?He/she is mine.
希望对你有帮助

追问：

还有后面啊 一个

追答：

Are these your pencils?Yes, they are.