So well         in 2009 that the world has agreed that it was the year of China.

A．did China perform

B．China has performed

C．was China performed

D．China is performing

120．1型控制阀由中间体、（）、半自动缓解阀、紧急阀等四部分组成。

A.加速缓解阀

B.调整阀

C.主阀

D.紧急二段阀