unit7动词与时态一

1、动词与时态（一）am(JScoreI believe I can do it best!我相信我可以做到最好!般现在时般现在时表示现在的一段时间内经常发生的动作、存在的状态例:He often helps me with my English.I like swimming very much.She is in the teachersoffice now.His brother reads En glish every morning.（一）一般现在时的构成谓语动词的人称变化：当主语是第一人称、第二人称或第三人称复数形式时，谓语动词要用动词原形。当主语是第三人称单数形式时，谓语动词用第三单

2、数形式，即动词词尾要加-S八或es 。例: We have four classes in the morning every day.They make progress every day.She likes singing very much.动词的第三人称单数形式变化可分为规则变化和不规则变化两种情况。规则变化 一般直接在动词词尾加s。例：ask asks/work works/get gets/stay stays 以字母s,x,ch,sh或o结尾的动词，在词尾直接加。例：watchwatches/wish wishes/fix fixes/do does/go goes/pass

3、passes 以辅音字母加y结尾的动词，要先变y变i再加eso例：try tries/study studies/cry cries/fly flies2不规则变化例：b ishavehas（二）一般现在时的句式转换1 -当句子中有be动词（am, is, are或情态助动词时，则把be动词或情态动词提到主语的前 面变成疑问句，在be动词或情态动词后加not变成否定句。例：She is a studentIs she a student ?She isn 4 a student.1 can swim.Can you swim ?I can t swim 2 当句子中既没有be动词，也没有情态动

4、词时，则在主语前加助动词do/does变成问句，在主语后谓语动词前加助动词do/does not变成否定句，助动词后的谓语动词要变成动词原 形。例： We get up at 7:00 every morning .Do you get up at 7:00 every morning ? We dont get up at 7:00 every morning ?She has a little brother Does she have a little brother ?She does nt have a little brother.（三）一般现在时的用法1表示经常性、习惯性或永久性

5、的动作或存在的状态5通常与副词sometimes, often,usually, always, every day （year, month） , once, twice, three times a day （week, month, year） 等表示频度的时间状语连用。例： They usually go to school by bike.I take the medicine three times a day .I get to school at 7:05 every morning .She telephones her parents once a week .Mary *

6、s father is a policeman .There are 50 students in my class.She is our maths teacher.My granny likes Beijing Opera very much .She can swim very well.2表示客观真理、科学原理、自然现象、现阶段存在的客观事实或格言、谚语等。例： The sun rises in the east and sets in the west every day .The earth moves around the sun .The man who has never b

7、een to the Great Wall is not a real man .Tomorrow is Tuesday .3 用于由 if, unless, as when, as soon as, until, till, after, before, while/whenever, whatever, even if, each time, the moment, every time, no mater how (what, whe n),so long as, on condition that等词引导的时间、条件、地点、让步、方式以及比较等状语从句中表示将来要发生 的动作或状态，其

8、从句多是一般现在时态，即“主将从现”。例: We will go to the zoo if it is fine tomorrow.She will tell me the news as soon as she sees her friends .They will go to work at this school when they leave college .11 llcome to see you whether he comes or not.We wontsee each other until the winter vocation comes.4表示安排或计划好的将来的动

9、作，这里的动词只能是表示移动的动词，如go/come/leave/start/arrive/begi n 等。例： The first class begins at 7:30 this evening.The bus starts at 5:30 in the morningThey leave here for Tianjin next Monday.5 表示状态或感觉的动词如 see, understand, feel, think, want, hear, find, have, be, love,like, hope, wish等，若它们表示现在发生的行为时，多用一般现在时而不用进行

10、时态。例：I am a teacher now.Now I understand why you didn t come here yesterday.Do you want to buy the cat now ?What do you think of our new teacher ?I love my friends very much.I wish you a good luck .I hope youll b*e back soon.般过去时一般过去时表示过去发生的动作或存在的状态，这种动作或状态可以是经常性的、习惯 性 的、也可以是一次性的或偶然性的。傍!| : He often

11、 got up late last year,She was a teacher when she was young,We met at the street yesterday.Did you write to your parents last month?（一）一般过去时的构成在一般过去时态的句了中，谓语动词、连系动词或助动词要用过去式形式。动词过去式的变 化有规则变化和不规则变化两种。1规则变化 一般在动词词尾直接加-ed。例：ask asked/work fworked/stay /stayedplay-play ed/ an swert an swered/wa nt rwan

12、ted 在以e结尾的动词后直接加d.例:likeflik ed/live /liv ed/love /lovedusaused/change rchanged/joke i jok ed 以辅音字母加y结尾的动词要变y以i再加-ed.例：studyrstudi ed/cry tcri ed/try itri edcarrytcarri ed/dry tdri ed但是以元音字母加y结尾动词直接加-ed. 以一个元音字母加一个辅音字母结尾的重读闭音节动词，要先双写最后一个辅音字母再加- ed.例：stopfstopped/shopfshopped/drop fdroppedplanrplann

13、ed/travel ftravell ed（特殊的 r 音节：prefertpreferr ed）2不规则变化许多动词的过去式及过去分词变化是不规则变化，而且大部分是常用动词。不规则动词的过 去式构成也有一点规律，如ow变成ew和own, i变成a和u, eep变成ept, ell变成old等 等，这 要靠仔细观察、反复诵读和认真记忆。例：am/isfwastbeenarerweretbeengiveigavetgivencometcameicome（二）一般过去时的句式转换。1. 当句子中有be动词（was, were）或情态助词的过去式时，则把be动词或情态动词提到主语的前面变成疑问句，在

14、be动词或情态动词后加not变成否定句。例： She was here yesterday. iWas she here yesterday? tShe was nt here yesterda y.He could do it. rCould he do it?tHe couldn t do it.2. 当句子中既没有be动词，也没有情态动词时，则在主语前加助动词did变成问句，在主语后谓语动词前加助动词did not变成否定句，助动词后的谓语动词要变成动词原形例：We got up at 7:00 yesterday morning.f Did you get up at 7:00 yes

15、terday morning?fWe didnt get up at 7:00 yesterday morning.She had a small box last year.f Did she have a small box last year?fShe didn t have a small box laesat ry.一般过去时的用法1.表示在过去某时间发生的动作或存在的状态,常*与yesterday, ago, last year(week,mon th,-) ,i n 1985, just now, on February 28, before, the last day( mon

16、 th, week, year )等表示 过去时间的状语或时间状语从句连用。例： We met each other in the street yesterday.Bob was born on May 2,1987.They worked hard all day at home last Sunday.Just now he called you and left a message.I didnhave breakfast this morning.We walked to get her hand in hand.When I was in the college I did morning exercises every day.Tom always got up very early and read book or did homework.They held a sport meeting last Saturday.2表示过去经常性或习惯性动作5可