when引导的时间状语从句和宾语从句的时态

我们知道,When引导的时间状语从句,表示当一个动作发生时,另一个动作同时发生。所以依据when时间状语从句的定义,应该主,从句中要有一个为进行时,或两个都为进行时（类似有：while,as,)如下例所示。When I saw her, she was typing a letter。When/(while) I was doing my homework, my mother was doing housework。宾语从句-时态 1·主句用一般现在时,从句可用任意时态。2·主句用过去时,从句用过去某个时态。3·主句用过去时,从句是真理时,只用一般现在时。宾语从句-连接词 1．连词that：只起连接作用,在从句中不作句子成分,也无词汇意义,在口语中或非正式文体中常被省略。He knew（that）he should work hard． 2．连词whether或if：它们起连接作用,在从句中不作句子成分,作“是否”解,口语中多用if。Do you know whether he will ride here at 8 tomorrow morning?3．连接代词who,whom ,whose,what, which：它们起连接作用,作句子成分,各有其自己的意义。The teacher asked the new student which class he was in?（which引导宾语从句,在从句中作定语,修饰class,意为“哪个”。） 4．连接副词when,where, why,how：起连接作用,分别作时间、地点、原因、方式状语,各有其自己的意义。I wonder where he got so much money．对他从哪里弄到那么多钱我感到疑惑。（where在从句中作地点状语,修饰got,意为“哪里；什么地方”。