He writes a letter every day.
(1)表示感知的动词：hear, feel, notice, recognize, see, taste, smell;
He wrote a letter yesterday.
(2)表示意愿、情感的动词：desire, dislike, forgive, hate, like, love, prefer, refuse, want, wish, fear, love, hate;
(3)表示思考、看法的动词：believe, doubt, expect, forget, hope, feel, mean, know, agree, realize, mind, recall, recollect, remember, trust, suppose;
He will write a letter tomorrow.
(4)表示所有、占有的动词：belong to, owe, own, possess, hold(容纳)；
(5)其他动词：cost, appear, concern, contain, consist, deserve, matter, seem。
He has written the letter.
I’d say whenever you are going after something that is belonging to you, anyone who is depriving you of the right to have it is criminal。
He had written the letter when I came.
He was seeing somebody creeping into the house through the open window last night。
He will have written the letter before I come.
(1)be going to表示现在的打算和意图；
(2)arrive, come, drive, go, leave, retire, return, set off, start, take off等表示移位的动词的进行体表示按计划肯定要发生的将来动作；
He is writing a letter now.
(3)be to (do)表示安排、计划、决定、命令或注定要发生的事，如：
Greater efforts to increase agricultural production must be made if food shortage is to be avoided。
He was writing a letter when I came.
(4)be about to (do)表示将要(做)，如：
Marlin is a young man of independent thinking who is not about to pay compliments to his political leaders。
He will be writing a letter when I come.
(5)be on the point /verge of (doing)表示“马上就要”，一般不与表示将来的时间状语连用；
(6)be, begin, come, depart, get off, go, leave, return, start的一般现在时表示按日历或时刻表要发生的将来动作或事件，如：
If you want your film to be properly processed, you’ll have to wait and pick it up on Friday, which is the day after tomorrow。
He has been writing for two hours.
②过去完成进行时：when I called,he had been writing a letter for two hours.
I don’t know where he will go tomorrow. 我不知道他明天去哪儿。(宾语从句)
I’ll tell him when you will ring again. 我告诉他你什么时候再来电话。(宾语从句)
I smell something burning.
比较：I’ll tell him when you ring again。你再打电话时我告诉他。(状语从句)
You look worried.
(8)在make sure, make certain, see (to it) 后的that从句中，谓语动词用一般现在时代替将来时，如：
This medicine tasts bitter to me.
See to it that you include in the paper whatever questions they didn’t know the answer to last time。
He has a book.
(include 不能用will include或其他形式)
Your hands feel cold.
I see a man standing there.
(1)by/between/up to/till +过去时间、since、by the time/when +表示过去发生情况的从句，主句用过去完成时。如：
He is a student.
We had just had our breakfast when an old man came to the door。
Between 1897 and 1919 at least 29 motion pictures in which artificial beings were portrayed had been produced。
He goes to school every day.
He writes a letter every day.
(2)by +将来时间、by the time/ when +谓语动词是一般现在时的从句，主句用将来完成时。如：
He always take a bus home.
By the time you arrive in London, we will have stayed in Europe for two weeks。
I hope her health will have improved greatly by the time we come back next year。
The sun rises in the east.
(3)by now、since +过去时间、in/during/for/over/the past/last few(或具体数字)years/days/months，主句用现在完成时， 但在it is +具体时间since/before这一句型中，主句更多的时候不用完成时。如：
He ,who is lazy is doomed to failure.=he, who is lazy is doomed to fail.
The changes that howe taken place place in air travel during the last sixty years would have seemed completely impossible to even the most brilliant scientists at the turn of the 19th century。
Honest is the best policy.
It is four years since John left school。
2.4.表将来：begin/start/arrive/go/come等动词用一般现在时表将来。Does he come tomorrow?
(4)在It is the +序数词/形容词最高级+that的定语从句中，谓语动词常用现在完成时。如：
It isn’t the first time that I have found myself in an embarrassing situation。
(5)在no sooner…than…, hardly/scarcely…when/before…句型中，主句常用过去完成时。
I saw him yesterday.
(6)其他与完成时连用的时间状语：all this while, all this year, for some time, so far, already, before, just, long, yet等。
He was born in 1978.
The company has been promising a rise in salary for ages, but nothing has happened。
Did you ever see her before?=Have you ever see her before?
The school board listened quietly as John read the demand that his followers had been demonstrating for。
It will rain tomorrow.
When I have money,I will buy a car.
②be going to=will
He is going to come.=he will come.
I have just finished my work.
I have met him several times.
I have lived here 10 years.
She has studied English since 2000.
注意：表“曾去过”的经历时，用“have been”而非“have gone”
He has gone toHong Kong.已经去了，现在人在香港；he has been to Hong Kong.曾去过，现在又回来了。
He had studied English for10 years before he left for the States.
He told me that he had seen the movies once.注意过去完成时不能单独存在，必须有一般过去时从句或表过去的时间副词短语连用方可体现出不同时间发生的两种动作。
I lost the book which she had given me.
He will have arrived in Chicago by this time tomorrow.
When you come ,everything will have been finished.
I am doing laundry.
He is coming today.=he will be coming today.
He was taking a bath when you called.
He was dying=he was going to die.=he was about to die.
He will be reading book this time tomorrow.
She has been working with this company for 5 years.
I had been sleeping when he came.
13.使用将来完成进行时的时机：主语+will have been+现在分词，译作“将一直在”，表一直到将来某时，仍将继续的动作。
I will have been studying English for ten yearsby the end of this year.
（for/during/in/through/down through） the （past/last）five years.=since five years ago.自从5年前起，这些短语与现在完成时或现在完成进行时连用。
I have been studying English for the past two weeks.
I have been studying English since I went to college.
He has lived here since 2000.
Peter has lived here since two years ago.
It is twenty years since he married.
I gave him a book.（主动）
①He was given a book by me.（被动）
②A book was given him by me.（被动）
They laugh at me.→I was laughed at by them.
Police looked into the case.→The case was looked into by police.
They don't love him.→He is not loved by them.
If he is here,I will beat him.
If he were here,I would beat him.(but he is not here)
If he had been here,I would have beaten him.kbut he was not here)
If he should be here,I (would/will)beat him.
If the cat were tosmile,I would pass out.
If the sun were to rise in the west,how surprised these sunflowers would be.
If he had done it,he would have felt sorry.→Had he done it.he would have felt sorry.
He should tell lies,i would punish him.→should he tell lies,i would punish him.
If he were lazy,he might fail.→were he lazy,he might fail.
If I had started saving then,I would have been able to buy a car now.
If=in case(that)/on condition that/provided/providing(that)/so long as/as long as/此类连词一般只能用于纯条件情况下，其引导的从句均为一般现在时。
In case he comes,let me know.
I will take the trip with you on condition that you bear the expense.
Iwill pardon him provided/providing(that)he acknowledges his mistake.
Any book will do as long as it is interesting.
注意：in case +(that)从句 万一……
In case of+名词 万一……
In case of an accident,don't panic=in case (that) an accident,don't panic.
If it （were not/but for+名词）+(for+名词/一般现在时that从句），主语＋（could/would/might/should)+not+原形动词
If it were not that he works hard,I wouldn't like him.=If itwere not for his hard work,…
=were it not for his hard work,…（要不是他努力工作，我才不喜欢他）
=but for his hard work,…
If it had not been(for+名词/一般过去时that从句），＋主语（would/could/might/should/ought to)+not+have+p.p.
If it had not been that he lent me the money,I could not have bought the book.=if it had not been for the money(which)he lent me,i could not have bought the book.=but for the money he lent me,i could not have bought the book.要不是他当初借钱给我，我就买不了那书了。
But for his help,I couldn't have done it.=without his help,I couldn't have done it.
I got up early,lest I miss the train.
注意：lest should=for fear that+主语+may+V.（表现在或将来的情况）
You muststudy hard lest you should fail the exam.=you must study hard for fear that you may fail the exam.=you must study hard for fear of failing the exam.
7.as if=as yhough译作“仿佛……”，均为副词连词，引导状语从句，使用时有三种时态：
It looks as if(as though) it is going to rain.
Mr.wang loves me as if(though)I were his own child.
He looked as if (though)nothing had happened.
7.4.as if或as though之后可接不定式，表示即将发生的状况。
She opened her lips ss if(as though)(she was going)to speak.
What if he should come?=what might happen if he should come?=what should we do if he should come?
What if it should rain?=what if it rains?=what may happen if it rains?
9.It is （about time/time/high time) +that从句的一般过去时译作“该是……的时候了”注意在使用本句型时that从句的动词要用一般过去时。It is time(that)he went to bed.（本句暗示现在该是睡觉时候了却没睡，其动作与现在事实相反故用一般过去时。）
It is high time we did it.
It is time our children learned some maners.
It is time he went to bed.=It is time for him togo to bed.
If only he were here=I wish he were here.
If only I had known it earlier.=I wish I had known it earlier.
I wish he were here.
I wish he had been here.=I would rather he had been here.
Ihope (that) he is safe.
Ihope he will beback.
I hope they are having a good time.
I hope they have finished the work.
13.I hope与祈使句的关系：I hope接that从句时，句中可使用助动词may，形成祈使句，此时将I hope that删掉，再将may置于that从句的主语之前，动词仍用原形，改句号为感叹号。
I hope that he may live long.→May he live long!
I hope you may pass the exam.→May you pass the exam!
I hope God may bless you.→May God bless you!→God bless you!
I hope the king may live long.→May the king live long!→ long live the king!
Iwish to travel abroad.=I hope to travel abroad.
I wish for a chance to try it.
I wish you a good time.=I hope (that) you (may)have a good time.
I wish my parents longevity.=I hope (that) my parents can live long.
①must have+p.p.一定曾经……he is learned,he must have recieved a good education.
②may have+p.p.可能曾经……he may have atayed up late last night.
③从cannot have+p.p.不可能曾经……he is honest,he cannot have stolen her money.
④表猜测的结构为疑问句时，要用Can…have…?句型之Can he have done it?
16.didn't need to do和need not have done的区别：
didn't need to V是表过去的事实，即“不必……”同时也没有如此做；但need not have +p.p.表与过去事实相反的虚拟语气，乃“本不必……但做了”
I had enough money,Ididn't needborrow any from him.（事实是没借钱）
Since you have enough money,you needn't have borrowedmoney from me.Whydid you still borrow some?（事实是借钱了）
He insisted on doing it that way.
注意insist on doing和persist in doing的区别是：insist on doing含有固执的意味；persist in doing含有能力坚持，不轻易放弃的意思。
It is my suggestion that he (should) study abroad.