--- Is Guo Peng your brother?
--- ______.

用am，is或are填空。
1.That's my father and this        my mother.
    They        my parents.
2.This is my friend and that        my sister.
3.  —_      she your sister?
    —Yes.she        .
4.—       he your brother?
   —No. He        my friend.
5.—          Guo Peng your brother?
   —Yes, he        .
6. I       his friend and he         my friend.
7. —         you Jack's brother?
    —No, I'm not.
8.These          my parents and those          my grandparents.