We had planned to finish the work before dark, but the heavy rain _____ us _____．

A．build, up

B．put, up

C．bake, up

D．hold, up

诊断螺杆泵故障可通过观察（）的变化来诊断油井工作状况。

A、套压和静压

B、流压和静压

C、油压和套压

D、油压和流压