用am, is或are填空。

1. She ____ a teacher. Her name ____ Wang Li.

2. I ____ a boy. My name ____ Li Ming.

3. —Who ____ this girl?

    —She ____ Li Mei.

4. —How old ____ you?

    —I ____ eleven.

5. —What ____ this? 

    —It ____ a bird.

6. —What ____ its name? 

    —Its name ____ Polly.

7. I ____ in Row Four. I ____ a girl.

8. David ____ a boy. He ____ twelve.

9. It ____ a cat. It ____ five.

10. You ____ a teacher. He ____ a teacher, too.

以下电解质平衡关系中哪些是错误的（）。

A.血浆、细胞间液及细胞内液的阴阳电荷数是相等的

B.血浆、细胞间液及细胞内液的渗透浓度是相等的

C.由于细胞膜的阻隔，细胞内外离子的种类及渗透浓度差别很大

D.毛细血管内外液的离子种类及浓度也有差别

E.血浆与组织间液的Na⁺、K⁺、Cl^-浓度相等