She ________ for 12 years by the time she graduates from the Foreign Language Institute．
A.has studied EnglishB.has been studying EnglishC.had studied EnglishD.will have been studying English在线课程D
本题考查将来完成进行时。“by+将来的时间”是将来完成时的标志，而“学习”这个动作是一直进行的，因此选D项。