文档介绍：八大时态
 一、 一般现在时：
：经常、反复发生的动作或行为及现在的某种状况。
： always, usually, often, sometimes, every week (day, year, month…), once a week, on Sundays,
：动词 原形 （如主语为第三人称单数，动词上要加（e）S）
：am/is/are+not;此时态的谓语动词若为行为动词，则在其前加don't,如主语为第三人称单数，则用doesn't，同时还原行为动词。
：把be动词放于句首；用助动词do提问，如主语为第三人称单数，则用does，同时，还原行为动词。
：. It seldom snows here.
He is always ready to help others.
Action speaks louder than words.
二、 一般过去时：
：过去某个时间里发生的动作或状态；过去****惯性、经常性的动作、行为。
：ago, yesterday, the day before yesterday, last week(year, night, month…), in 1989, just now, at the age of 5, one day, long long ago, once upon a time, etc.
：be动词；行为动词
：was/were+not;在行为动词前加didn't，同时还原行为动词。
：was或were放于句首；用助动词do的过去式did 提问，同时还原行为动词。
：She often came to help us in those days.
I didn't know you were so busy.
三、 现在进行时：
：表示现阶段或说话时正在进行的动作及行为。
：now, at this time, these days, etc.
：am/is/are+doing
：am/is/are+not+doing.
：把be动词放于句首。
： How are you feeling today?
He is doing well in his lessons.
四、 过去进行时：
：表示过去某段时间或某一时刻正在发生或进行的行为或动作。
：at this time yesterday, at that time或以when引导的谓语动词是一般过去时的时间状语等。
：was/were+doing
：was/were + not + doing.
：把was或were放于句首。
：At that time she was working in a PLA unit.
When he came in, I was reading a newspaper.
五、 现在完成时：
：过去发生或已经