while___the book,he noddded from time to time.A read B he reads C reading D reads

问题描述:

while___the book,he noddded from time to time.A read B he reads C reading D reads
为什么?

C 当主语一致,且有连词,可省略主语与be动词.主语he与reading为主动关系,所以填reading为什么read要加 ing因为省略了be动词,原句相当于while he was reading the book,he noddded from time to time为什么是reading而不是别的谢谢如果没有he,需用ing形式,AD不对,如果选B,应该是while he was reading the book,he noddded from time to time。while引导从句一般用进行时。