Question

   , I think, and all the problems could be settled.

A．If you make more efforts

B．Making more efforts

C．A bit more effort

D．To have made more efforts

Answer 1

C

句中有并列连词and，故应择C项。其中名词短语相当于一个祈使句，完整的句子为：Make more efforts, I think, and all the problems could be settled.如A , and要删去。