I don't know when Lucy __ to see me.When she ___,please tell me.请_英语解答

I don't know when Lucy __ to see me.When she ___,please tell me.
请问前后两个when有什么不同的用法?为什么要选A?
I don't know when Lucy __ to see me.When she ___,please tell me.
A:will come,comes B:will come,will come C:comes,comes D:comes,will ocme

人气：112 ℃　时间：2019-08-19 03:36:49

解答

第一个句子是宾语从句,主句是现在时,所以从句可以根据需要用任何时态；如果主句是过去时,则从句也必须用过去时；
第二个句子是if引导的条件状语从句,状语从句的特点是时态,主句现在,从句现在；主句过去,从句过去；主句将来,从句现在.
所以,选A.