The doctor suggested he ________with a serious disease and that he ________to hospital at once.

A．be infected；be sent

B．was infected；be sent

C．should be infected；was sent

D．be infected；was sent

KY-310型牙轮钻机液压系统采用（）向系统提供压力油。

A.齿轮泵

B.双联齿轮泵

C.双齿轮泵

D.双叶片泵