时间状语从句时态问题: 1 )主过从过(一致):While I was doing my homework, the telephone rang.2 )“主将从现”: He will call me as soon as he ___B___ to Beijing.A. get B. gets C. got D. is getting 条件状语从句时态问题: 1 )“主将从现”: ● I will go on a picnic with my friend if it _ B___ tomorrow.A. won’t rain B. doesn’t rain C. don’t rain D. isn’t raining if 是否 = whether (引导宾语从句) if 假如 (引导条件状语从句,遵循“主将从现”) I don’t know if it _ ____ tomorrow. If it _________, I will not go to movie.A. rains; rains B. will rain; will rain C. rains; will rain D. will rain; rains● 第一个 if 为“是否”的意思,引导的是宾语从句。宾语从句的时态问题:主句为一般现在时,从句用适当时态,从句的时间是 tomorrow, 因此第一个空应是: will rain 。第二个 if 为“假如”的意思,引导的是条件状语从句,遵循“主将从现”原则,因此第二个空应该用一般现在时: rains 。答案: D