A. 根据所给汉语，写出句中所缺的词语。

1. You could               (自愿服务)in a hospital.

2. I'd like to help               (无家可归)people.

3. We often visit               (小学的，初级的)schools and help the teachers.

4. A girl won a million dollars in the              (抽奖).

5. Before you borrow something from a friend, you'd better ask his or her 　     　 (许可)

B. 根据句意填空。

1. Whose is that book? It              be Liu Mei's.

2. I don't like art at all. But my sister              art to music.

3.               are from Italy. They like to eat pizza.

4. He can't walk and he sits in a              .

5. It's easy to be angry but it's hard to              .

概念模型中最为常用的是1976年由( )提出的实体—联系方法。

A．
P．
S．Chen
B．Martin
C．
F．Codd
D．
H．Inmon