先生（ ）わからない問題が学生にわかるわけがない。
A．なら
B．だから
C．だけが
D．でさえ
参考答案：D
在Access扣，参照完整性规则不包括
A．更新规则
B．查询规则
C．删除规则
D．插入规则
用所给词的适当形式填空。
1. Kangaroos are _____ (play) and chimpanzees are _____ (noise).
2. I was _____ (surprise) to find hardly anyone in the zoo.
3. Visiting zoos are like _____ (live) textbooks for young people.
4. He _____ (use) to be _____ (call) "Little Tiger".
5. Liu Xiang's success is an _____ (inspire) to us all
