(一)一般现在时与现在进行时
(1)一般现在时用以说明客观事实,或用于强调动作的永久性、经常或反复性。而现在进行时强调动作正在进行,因此它表示动作含有暂时性(即动作的持续时间是有限的)和未完成性。
e.g. The writer writes children’s stories.那位作家是写儿童小说的。(说明客观事实)
The writer is writing a story.那位作家现在正在写一个故事。
She is kind.她很善良。(指她一贯心地善良)
She is being kind.她现在显得很善良。(表示暂时性,平时她并不善良)
Tom types his own letters.汤姆自己用打印机打信。(说明经常性)
Tom is typing his own letters.汤姆自己正在用打印机打信。(表示暂时性、未完成)
(2)有些动词,如:like, hate, believe, guess, know, mean, remember, hear, see, sound, seem等,不能用于进行时,即使表示说话时正在进行的动作也通常用一般现在时。
e.g. I know him.我认识他。(不说:I am knowing him.)
Jenny likes this green coat.珍妮喜欢这件绿大衣。(不说:Jenny is liking…)
某些动词既可用于一般现在时,又可用于现在进行时,但意义有所不同。试比较:
I feel (=think, believe) you are right/there’s something wrong.我觉得(=认为、相信)你是对的/有点不对头。(这个意思不用进行时 )
I’m feeling cold.我觉得冷。
What are you thinking about?你在想些什么。
What do you think of the idea?你认为这个主意怎样?
I think you’re right.我认为你是正确的。
He is smelling the meat.他正在闻肉。
The meat smells bad.这肉有臭味了。
I see (=understand) what you mean.我明白你的意思。
I see the fish .我看见那条鱼了。
I’m seeing (=consulting ) a doctor.我正在看医生(即看病)。
I’m seeing (=visiting) a friend of mine.我正在看一个朋友。
某些表示身体感觉的词(如 hurt, ache, feel等),用一般现在时和现在进行时没有多大差别,只是进行时更生动、更有感情色彩。
e.g. How do you feel today? (or: How are you feeling today?) 你今天的感觉怎样。
My head is aching.(or: My head aches.) 我头疼。
I feel cold.=I’m feeling cold.我觉得冷。
(3)一般现在时说明事实,一般不带感情色彩;现在进行时与always, often, frequently等词连用时带有感情色彩。
e.g. He always asks questions.他总是提问题。(无感情色彩)
He is always asking questions.他老爱提问题。(表示强烈的感情色彩)
Don’t be complaining all the time.别老是抱怨个不停。
She’s always blaming others.她总是在埋怨别人。
(二)there be 句型
(1)定义:There be句型表示某处存在某物或某人。
(2)结构:(1) There is +单数可数名词/不可数名词+地点状语.
(2) There are+复数名词+地点状语.
e.g. There is a bank on the street corner.
There is some milk in the bottle.
There are many trees and flowers in the park.
(3)there be 句型与have句型的区别:
There be 句型和have都表示“有”的含义。区别如下:There be表示“某处存在某物或某人”;have表示“某人拥有某物/某人”,它表示所有、拥有关系。
e.g. There is a computer on the desk.
I have a computer.
(4)句型转化。
a.变成否定句
There be句型的否定式的构成和含有be动词的其它句型一样,在be后加上not或no即可。注意not和no的不同:not是副词,no为形容词,not a/an/any + n. 相当于no+ n.。
e.g. There are some pictures on the wall. →There aren't any pictures on the wall. =There are no pictures on the wall.
There is a bike behind the tree. → There isn't a bike behind the tree. =There is no bike behind the tree.
b.变成一般疑问句
There be句型的一般疑问句变化是把be动词调整到句首,再在句尾加上问号即可。但同时要注意:当肯定句中有some时,要将其改为any(否定变化也一样)。
There is some water on Mars. → Is there any water on Mars?
There are some fish in the water. →Are there any fish in the water?
c.特殊疑问句
对主语提问:当主语是人的时候,则用who 引导,当主语是物的时候,则用what 引导。注意:无论原句的主语是单数还是复数,对之提问时一般都用be的单数形式(回答时却要根据实际情况来决定)。如:
There are many things over there. →What's over there?
There is a little girl in the room.→Who is in the room?
对地点状语提问:则用where 引导。如:
There is a computer on the desk. → Where is the computer?
There are four children on the playground. →Where are the four children?
(5)there be 句型的主谓一致:
There be 结构中的be动词要和后面所跟名词保持一致,遵循就近原则。
e.g. There ___ any rice in the bowl.
A. are B. is C. isn’t D. aren’t
There ___ many apples on the tree last year.
A. have been B. were C. are D. is
(三)祈使句
(1)定义:用于表达命令、请求、劝告、警告、禁止等的句子叫做祈使句,祈使句最常用于表达命令,因此在学校文法中也常称为命令句。 祈使句对象(即主语)是第二人称时,通常都省略。祈使句的动词都为一般现在时,句末则使用句号来表示结束。
e.g. Go and wash your hands.
Be quiet, please.(Please be quiet.)
Be kind too your sister.
Watch your steps.
Look out!Danger!
No parking.
祈使句也常把主语“You”表达出来,使对方听起来觉得柔和些,例如: You go and tell him, Chris.
(2)祈使句的肯定句式
1.行为动词原形+其它成分。
Make sentences after the model.根据例句造句。
2.Be动词+其它成分(形容词、名词或介词短语等)
Be careful when crossing the street.过马路时要小心。
3.Let+宾语+动词原形+其它成分。
Let him go back now.让他现在回去吧。
(3)祈使句的否定句式
祈使句的否定句式,通常情况下在句首加上Don’t或Never:
1.在祈使句的肯定句式前加Don’t,构成Don’t+行为动词原形+其它成分。
Don’t say that again!=Never say that again!别再那样说了!
2.在Be动词引起的肯定祈使句前加Don’t,构成Don’t be+其它成分(形容词、名词或介词短语等)。例如:Don’t be careless.不要粗心。注意:在这种句型中be不能省略;否定副词not不可置于be之后。
3.Let引起的祈使句的否定形式有两种:(1)Let开头的祈使句,如果后面跟第一、第三人称名词或代词的宾格,可在Let前加Don’t,也可在Let后宾格的名词或代词后面加not。(2)如果以Let’s开头的祈使句,必须在Let’s后加not。
Don’t let me go with her tomorrow.=Let me not go with her tomorrow.不要让我明天跟她一起去。
二、课堂练习
1.The children _B__ football.
A. is playing B. are playing C. play the D. play a
2.___C___go and help her.
A. Let's me B. Let's us C. Let's D. Let's to
3.-What are they doing? -They are __C_ things away.
A. put B. puting C. putting D. carry
4. It’s 6 o’clock in the morning. He __C__.
A. get up B. gets up C. is geting up D. is getting up
5. We _C_any Chinese classes on Friday.
A. are having B. aren’t having C. don’t have D. are have
6.Where _C_ he __ from?
A. is come B. do come C. does come D. is from
7.Please help me carry it, __B____?
A. will I B. will you C. shall I D. shall we
8.Kate, ____A___ your homework here tomorrow.
A. bring B. brings C. to bring D. bringing
9.--What__D___on the shelf?
---There are some books.
A be B am C are D is
10.--Is there a garden in the yard?
---Yes,there is .And there _A__grass in it.
A is so much B are so many C is so many D are so much
11.Will you please read it again more slowly? (改为祈使句)
__Read__ __it__ again more slowly, please.
12.If you don't listen to me, I'll go. (改为同义句)
__Listen__ __to___ me, or I’ll go.
三、作业
1.--__B__you ___ the blackboard? --Yes, I am.
A. Can, clean B. Are cleaning C. Do clean
2.I want __B_ homework now.
A. doing B. to do C .to do my D. do my
3. Look! The twins _C__ their mother do the housework.
A. are wanting B. help C. are helping D. are looking
4.Don't make so much noise, ___A___?
A. will you B. won't you C. shall we D. do you
5.__D__ me the truth, or I'll be angry.
A. Telling B. To tell C. Told D. Tell
把下面句子改为否定句和疑问句:
There is some water in the bottle.
There are some books on the shelves.