— Each of the students working hard at their lessons the book. — So have I.A. is readin

问题补充：

— Each of the students, working hard at their lessons, the book. — So have I.

A. is reading

B. has read

C. reading

D. reads

答案：

A. is reading

(答案→)B. has read

C. reading

D. reads

解析：此题将主谓一致和时态结合在一起进行考查。上一句的主语为each of the students 是单数，再结合下文的回答so have I，由此，可知上句应该用完成时态。