闸阀的传动形式有手轮式、正齿轮式、伞齿轮式和（）.
A.电动式
B.电磁式
C.自力式
D.弹簧式
参考答案：A
下列实验操作不正确的是[ ]
A．
B．
C．
D．
用所给动词的适当形式填空。
1. I have been looking forward to _____ (watch) the performance by the New Ocean Waves.
2. So far the famous band _____ (make) 8 hit CDs.
3. The Smiths have _____ (go) to Japan and they will be back to China next month.
4. "Have you ever _____ (are) to America?" John asked me.
5. The cute girl _____ (write) several English novels since last term.
