It is three years () I seudied Endlish.A.when B.since C.as D.before
问题描述：
It is three years () I seudied Endlish.A.when B.since C.as D.before
答
选B理由：It is three years since I studied English.自从我学习英语以来已经三年了.（从过去学习英语的动作起已经三年了,）since 后是过去时另外,since也可以加现在完成时：It is three years since I have studie...