Think and write. （根据主语人称，用be动词的正确形式填空）

1. —             you a boy?

    — No, I          not.

2. The girl _____ Jack's sister.

3. The dog _____ tall and fat.

4. The man with big eyes____ a teacher.

5. ____     your brother in the classroom?

6. — Where _____ your mother?

    — She            at home.

7. How _____ your father?

8. Mike and Liu Tao _____ at school.

9. Whose dress _____ this?

10. Whose socks _____ they?