By the time you arrive this evening,____ for two hours.

问题描述:

By the time you arrive this evening,____ for two hours.
A.I will study
B.I will have been studied
C.I had studied
D.I will have been studying
B和D区别在哪儿啊?

选D
“by the time +将来时间”,用于将来完成时[will have done]或将来完成进行时[will have been doing],排除A,C
又由于B项是表示被动的,错误,故选D