They are his sister and brother.把his sister and brother提问
问题描述：
They are his sister and brother.把his sister and brother提问
答
Who are they?
答
Who are they ?
祝你学习进步，更上一层楼！ (*^__^*)
不明白的再问哟，请及时采纳，多谢！
答
Who are these/they?
答
who are his sister and brother?