I was supposed ____ her, but I failed.

A．to help

B．to have helped

C．to be helping

D．will help

司钻法压井在第二循环周压井液注满钻具内，（压井钻井液由井口至钻头），立管压力由（）下降到终了循环立管总压力。

A.关井立压

B.关井套压

C.注满钻具内

D.初始循环立管总压力