英語的時態(tài)（tense）j是一種動詞形式,不同的時態(tài)用以表示不同的時間與方式.
下面就英語中常見的八種基本時態(tài)進行闡述,其它的時態(tài)都是在這八種時態(tài)的基礎(chǔ)上結(jié)合而成的.
一、 一般現(xiàn)在時：
1.概念：經(jīng)常、反復(fù)發(fā)生的動作或行為及現(xiàn)在的某種狀況.
2.時間狀語： always, usually, often, sometimes, every week (day, year, month…), once a week, on Sundays,
3.基本結(jié)構(gòu)：動詞 原形 （如主語為第三人稱單數(shù),動詞上要加（e）S）
4.否定形式：am/is/are+not;此時態(tài)的謂語動詞若為行為動詞,則在其前加don't,如主語為第三人稱單數(shù),則用doesn't,同時還原行為動詞.
5.一般疑問句：把be動詞放于句首；用助動詞do提問,如主語為第三人稱單數(shù),則用does,同時,還原行為動詞.
6.例句：. It seldom snows here.
He is always ready to help others.
Action speaks louder than words.
二、 一般過去時：
1.概念：過去某個時間里發(fā)生的動作或狀態(tài)；過去習慣性、經(jīng)常性的動作、行為.
2.時間狀語：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.
3.基本結(jié)構(gòu)：be動詞；行為動詞
4.否定形式：was/were+not;在行為動詞前加didn't,同時還原行為動詞.
5.一般疑問句：was或were放于句首；用助動詞do的過去式did 提問,同時還原行為動詞.
6.例句：She often came to help us in those days.
I didn't know you were so busy.
三、 現(xiàn)在進行時：
1.概念：表示現(xiàn)階段或說話時正在進行的動作及行為.
2.時間狀語：now, at this time, these days, etc.
3.基本結(jié)構(gòu)：am/is/are+doing
4.否定形式：am/is/are+not+doing.
5.一般疑問句：把be動詞放于句首.
6.例句： How are you feeling today?
He is doing well in his lessons.
四、 過去進行時：
1.概念：表示過去某段時間或某一時刻正在發(fā)生或進行的行為或動作.
2.時間狀語：at this time yesterday, at that time或以when引導(dǎo)的謂語動詞是一般過去時的時間狀語等.
3.基本結(jié)構(gòu)：was/were+doing
4.否定形式：was/were + not + doing.
5.一般疑問句：把was或were放于句首.
6.例句：At that time she was working in a PLA unit.
When he came in, I was reading a newspaper.
五、 現(xiàn)在完成時：
1.概念：過去發(fā)生或已經(jīng)完成的動作對現(xiàn)在造成的影響或結(jié)果,或從過去已經(jīng)開始,持續(xù)到現(xiàn)在的動作或狀態(tài).
2.時間狀語：recently, lately, since…for…,in the past few years, etc.
3.基本結(jié)構(gòu)：have/has + done
4.否定形式：have/has + not +d one.
5.一般疑問句：have或has.
6.例句：I've written an article.
It has been raining these days.
六、 過去完成時：
1.概念：以過去某個時間為標準,在此以前發(fā)生的動作或行為,或在過去某動作之前完成的行為,即“過去的過去”.
2.時間狀語：before, by the end of last year(term, month…),etc.
3.基本結(jié)構(gòu)：had + done.
4.否定形式：had + not + done.
5.一般疑問句：had放于句首.
6.例句：As soon as we got to the station, the train had left.
By the end of last month. We had reviewed four books
七、 一般將來時：
1.概念：表示將要發(fā)生的動作或存在的狀態(tài)及打算、計劃或準備做某事.
2.時間狀語：tomorrow, next day(week, month, year…),soon, in a few minutes, by…,the day after tomorrow, etc.
3.基本結(jié)構(gòu)：am/is/are/going to + do；will/shall + do.
4.否定形式：was/were + not; 在行為動詞前加didn't,同時還原行為動詞.
5.一般疑問句：be放于句首；will/shall提到句首.
6.例句：They are going to have a competition with us in studies.
It is going to rain.
八、 過去將來時：
1.概念：立足于過去某一時刻,從過去看將來,常用于賓語從句中.
2.時間狀語：the next day(morning, year…),the following month(week…),etc.
3.基本結(jié)構(gòu)：was/were/going to + do；would/should + do.
4.否定形式：was/were/not + going to + do;would/should + not + do.
5.一般疑問句：was或were放于句首；would/should 提到句首.
6.例句：He said he would go to Beijing the next day.
I asked who was going there .
幾種常見時態(tài)的相互轉(zhuǎn)換
英語中的幾種時態(tài)在一定情況下可以互相轉(zhuǎn)換,以下是幾種常見的轉(zhuǎn)換形式：
一、 一般過去時與現(xiàn)在完成時的轉(zhuǎn)換
在現(xiàn)在完成時中,延續(xù)性動詞能與表示一段時間的狀語連用,瞬間動詞卻不能.但是,可用別的表達方式：①瞬間動詞用于“一段時間 + ago”的一般過去時的句型中；②瞬間動詞可改成與之相對應(yīng)的延續(xù)性動詞及短語,與一段時間連用；③瞬間動詞用于“It is + 一段時間 + since + 一般過去時”的句型中,表示“自從……以來有……時間”的意思,主句一般用it is來代替It has been;④瞬間動詞用于“Some time has passed since + 一般過去時”的句型中.請看：
A. He joined the League two years ago.
B. He has been in the League for two years.
C. It is two years since he joined the League.
D. Two years has passed since he joined the League.
二、 一般現(xiàn)在時與現(xiàn)在進行時的轉(zhuǎn)換
在一般現(xiàn)在時中,at加上名詞表示“處于某種狀態(tài)”,如at work（在工作）, at school（上學、上課）等.此短語可與進行時態(tài)轉(zhuǎn)換.請看：
Peter is at work, but Mike is at play.
Peter is working, but Mike is playing.
三、 現(xiàn)在進行時與一般將來時的轉(zhuǎn)換
在現(xiàn)在進行時態(tài)中g(shù)o, come, leave, start, arrive等動詞常與表示將來的時間狀語連用表示將要發(fā)生的動作.如：I am coming, Mum! 意為“我就來,媽媽!”請看：
The train is leaving soon.
The train will leave soon.
四、“be going to+動詞原形”與“will(shall)+動詞原形”結(jié)構(gòu)的轉(zhuǎn)換
“be going to+動詞原形”、表示打算、計劃要做的事；將來時“will(shall)+動詞原形”結(jié)構(gòu)在書面語中,當主語為第一人稱時,常用助動詞shall.在口語中,所有人稱都可以用will.請看：
We are going to visit the Great Wall next Sunday.
We shall visit the Great Wall next Sunday.