大全SECTION A-23

Ideally, the professional career diplomat
should help in the ongoing maintenance of an effective American foreign
policy despite changes in administration.

(A) in the ongoing
maintenance of

(B) in the
maintaining of

(C) maintain

(D) to maintain
and continue（C）

(E) the
maintenance of

答案是C

请问help后面为什么不是接to do 选D呢？

谢谢啦～

help后可加可不加 一般不加

不选D是因为maintain和continue意思重复了