--Could you please let me know when you come to Nanjing?--Ok.I______you before I______

问题描述:

--Could you please let me know when you come to Nanjing?--Ok.I______you before I______
A.will call;will arrive B.had called;arrived C.will call;arrive D.call;arrive

C.will call;arrive
句意:---你能否让我知道你什么时候离开南京?
---好的,我离开之前会打电话告诉你
before后的动词是发生在前的动作,所以用一般现在时表将来,从句用一般现在时表将来,主句用将来时!这遵循“主讲从现”原则!