初中英语句子结构及作用

句子的基本结构
一、句子的基本成分
句子的基本成分有以下几种：主语、谓语、宾语、表语、定语、状语、补语、同位语.
1、主语：句子的主体,全句述说的对象.一般由名词、代词、不定式、动名词或从句担当,位于句首.
The boy needs a pen.
Smoking is bad for you.
2、谓语：说明主语的动作或状态.由动词或系动词加表语担任,常置于主语后.
The train leaves at 6 o’clock.
She is reading.
3、宾语：表示动作的对象.一般由名词或代词担当,常置于谓语后.
He won the game.
He likes playing computer.
4、表语：用以表述主语的特征、状态、身份等.一般由名词或形容词担任,置于系动词之后.
He is a student.
We are tired.
注意：除了be 系动词外,还有一些动词也可以用作系动词,
1)表感官的动词: feel, smell, taste, sound, look, appear, seem 等.
2)表转变变化的动词: become, get, grow, turn, go等.
3)表延续的动词: remain, keep, hold, stay, rest等.
5、定语：对名词或代词起修饰、限定作用的词、短语或句子.
The black bike is mine.（形容词）
The boy in blue is Jim.（介词短语）
I have nothing to do today.（动词不定式）
注意：1、当定语修饰不定代词如：nothing , anything , everything , something 等时,定语要放在其后作后置定语.例如： I tell him something interesting.
2、不定式、短语或从句作定语时,也放在被修饰的名词之后.例如：
The boys who are in the room are playing games.
6、状语：用以修饰adj. /v. /adv.及全句,位置灵活.
1、修饰形容词或副词时,通常位于被修饰的词之前；
I am very sorry.
2、表示时间、地点、目的的状语一般位于句子两头,强调时放在句首.
In order to cheer him up, I told him the truth.
They are writing English in the classroom.
3、一些表示不确定时间（如：often）或程度（如：almost）的副词状语通常位于be动词、助动词、情态动词之后,动词之前.
We often help him.
He is always late for class.
7、补语：补充说明宾语的情况.由n./adj./介宾/分词/不定式等担任.常位于宾语后.
He made me sad.（形容词）
She asks me to take an umbrella.（不定式）
The war made him a soldier.（名词）
I find him at home.（介词短语）
I saw a cat running along the wall.（分词）
8、同位语：同位语是句子成分的一种, 它位于名词、代词后面, 说明它们的性质和情况, 它可以由名词、代词、名词性短语或从句充当.
Tom, our monitor, is a handsome boy.
I myself will do the experiment.
She is the oldest among them six.
二、句子的基本分类
1、按使用目的,句子可分为陈述句、疑问句、祈使句和感叹句.
1）陈述句：说明一个事实或陈述一种看法.例如：
Light travels faster than sound. 光比声传播速度快.（说明事实）
The film is rather boring. 这部电影很乏味.（说明看法）
2）疑问句：提出问题.有以下四种：
a. 一般疑问句：
Can you finish the work in time?
b. 特殊疑问句：
Where do you live?
c. 选择疑问句：
Do you want tea or coffee?
d. 反意疑问句：
He doesn't know her, does he?
3）祈使句：提出请求,建议或发出命令.例如：
Don't be nervous!
4）感叹句：表示说话人惊奇、喜悦、愤怒等情绪.例如：
What good news it is!
2、按其结构,句子可以分为以下三类：
1）简单句：只包含一个主谓结构句子叫简单句.例如：
She is fond of collecting stamps.
2）并列句：包含两个或两个以上主谓结构的句子叫并列句,句与句之间通常用并列连词或分号来连接.例如：
The food was good, but he had little appetite.
3）复合句：包含一个主句和一个或几个从句的句子叫复合句,从句由从属连词引导.例如：
The film had begun when we got to the cinema.
三、句子的基本结构
1、简单句
1. Things changed.
2. Trees are green.
3. We don’t like children.
4. He gave his sister a piano.
5. I found the book interesting.
2、并列句
This is me and these are my friends.
They must stay in water, or they will die.
It’s not cheap, but it is very good.
It was late, so I went to bed.
四、句子的扩写
1. The children played.
Lots of lovely children from China played happily in the park this morning.
2. The boy lent me a book.
The kind boy in blue coat lent me a very interesting book several days ago, and I love it so much.
句子的基本结构综合训练
一、指出下列划线部分的基本成分.
1. Our school is not far from my home.
2. It is a great pleasure to talk with you
3. All of us considered him honest.
4. Grandma told me an interesting story last night.
5. Her job is to look after the babies.
6. We need a place twice larger than this one.
7. He goes to school by bike.
8. The man over there is my old friend.
9. What he needs is a book.
10. I must leave right now.
二、指出下列句子属于哪种基本句子结构.
1. My grandfather bought me a pair of sports shoes.
2. He broke a piece of glass.
3. He asked us to sing an English song.
4. We will make our school more beautiful.
5. Trees turns green in spring.
6. He came finally last night.
7. Her voice sounds sweet.
8. The meeting will be held in the meetingroom.
9. Mary handed her homework to the teacher.
10. He made it clear that he would leave the city.
三、写出下列句子.
1、她学习很努力.
2、我昨天早上遇见了Lily.
3、五年前我住在北京.
4、你必须在两周以内看完这些书.
5、布朗夫人看起来很健康.
6、这个主意听起来很有趣.
7、我爸爸上个月给我买了一辆崭新的自行车.
8、他的父母给他取名为John.
9、这个学校有一名音乐老师和一名美术老师.
10、我认为他聪明又有趣.
四、扩展下列句子.
1. I went to school.
2. I got a book.
3. He left.