内容正文:
Welcome unit语法:句子成分和基本句型
句子成分
构成句子的各个部分叫做句子成分。句子成分有主语和谓语、表语、宾语、定语、状语、补足语和同位语。
1)主语(subject)
一般由名词、代词、不定代词或相当于名词的单词或短语来充当,也有从句充当的现象。大多数主语都在句首。比如:
1. The room is very clean. (名词)
2. We often speak English. (代词)
3. To teach them English is my job.(动词不定式)
4. Swimming is good for our health. (动名词)
5. What we need is food. (从句)
6. The poor are everywhere in some countries. (the +形容词)
2)谓语(predicate)
谓语说明主语所做的动作或具有的特征和状态,说明主语“做什么”,“是什么”,“怎么样”。谓语必须是动词,体现时态和语态,一般放在主语之后。谓语分简单谓语和复合谓语:
1、简单谓语:由一个动词或动词短语构成。
如: He practices running every morning.
2、复合谓语:
a.由情态动词+动词原形或其他助动词加动词某种形式构成。
如:He can speak English.
b. 助动词:帮助构成时态和语态,不同时态有不同的助动词,后加动词的某种形式构成谓语。
He doesn't like speaking Chinese.
I have seen the film before.
He didn't finish his homework last night.
3) 表语(predicative)
表语用以说明主语是什么或怎么样,它一般位于系动词之后,构成主系表结构,说明主语的状况,性质,特征等。它由名词、代词、数词、形容词、动词不定式及短语、副词、介词短语等充当。
常见的系动词:
1. 表状态:be
2. 表感官:look, sound, smell, taste, feel
3. 表变化:become, grow, turn, fall, get, go