问题
选择题
, 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
答案
答案：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。