主从句时态不一致的情况有哪些?比如if引导的条件状语从句,还有呢?

主从句时态不一致的情况有哪些?比如if引导的条件状语从句,还有呢?

一.状语从句
1.主句为一般将来时或由情态动词表示将来的动作时,if引导的条件句及when; as soon as; before; after; until 等引导的时间状语从句应用一般现在时代替一般将来时.例如:
If it doesn’t rain tomorrow,we’ll go to climb the hill.
I won’t leave until you agree with me.
2.主句为一般将来时或由情态动词表示将来的动作时,though; although; no matter what/how/when/where引导的让步状语从句也应用一般现在时代替一般将来时.
No matter who comes,I will help him.
3.主句为一般将来时或由情态动词表示将来的动作时,the more…引导的比较状语从句,也应用一般现在时代替一般将来时.例如:
The harder you study,the better your English will be.
The more trees we plant,the more beautiful our environment will be.
4.since引导的时间状语从句,用一般过去时,主句则用现在完成时(It’s…since….例外).
Uncle Wang has worked in the factory since it opened in 1982.
5.主句为过去时,状语从句也应用过去时态的某种形式.
When I was a child,Father had told me that story.
6.当主从句的动作均发生在过去时,注意含when,while引导的时间状语从句的主从句时态一致性的确定方法.
a)主句中动词动作先于从句中动词动作发生,且进行的时间较长时,主句用过去进行时,从句用一般过去时.例如:
The teacher was telling us a story when the headmaster came in.
b)从句中动词动作先于主句中动词动作发生,且进行的时间较长时,从句用过去进行时,主句用一般过去时.例如:
When the students were having a meeting,the teacher came in.
Last Sunday I met Lin Hong when I was walking in the street.
c)若主从句动作开始时间不存在先后关系(即同时发生)或无所谓先后时,主从句可同时使用过去进行时.例如:
While Han Mei was sweeping the floor,Lucy was carrying water.
d)主句动作和从句动作都已完成,则先发生的动作可用过去完成时态,后发生的动作用一般过去时态.例如:
When they got to the cinema,the film had been on for five minutes.
二、宾语从句
1.主句为一般现在时态时,从句可用各种适合的时态.例如:
I hear my parents will come back in two months.
2.主句为一般过去时态时,从句应用过去时的某种相应形式.
a)从句动作已完成,则从句可用过去完成时态或一般过去时态.例如:
Jim said that he heard from his brother two days ago.
Ann told us that she had seen that film.
b)从句动作正在进行时,从句应用过去进行时态.例如:
He didn’t tell us whether they were planting trees.
c)从句动作尚未发生,则从句用过去将来时态.例如:
Didn’t you know when they would start?
注意:
1)当从句表示客观真理或事实及自然现象时,其时态不应受主句的限制,而用一般现在时态.例如:
Our teacher told us the earth travels around the sun.
2)if 可表示“如果”之意,引导条件状语从句,也可表示“是否”之意引导宾语从句;when表示“当----时侯”之意,引导时间状语从句,也可表示“何时”引导宾语从句.
I don’t know if he will come today.If he comes,I’ll ring you up.
Please tell me when you will come.When you come,please let me know.