内容正文:
Unit1 Back to school
1.2 Grammar:句子成分和句子结构
一.句子成分
句子成分的定义:构成句子的各个部分叫做句子成分。句子成分有主要成分和次要成分;主要成分有主语和谓语;次要成分有表语、宾语、定语、状语、补足语和同位语。
1. 主语
主语是一个句子所叙述的主体,一般位于句首。但在there be结构、疑问句(当主语不疑问词时)和倒装句中,主语位于谓语、助动词或情态动词后面。主语可由名词、代词、数词、不定式、动名词、名词化的形容词和主语从句等表示。
指出下列句子中的主语及它的性质:
①During the 1990s, American country music has become more and more popular.
②often speak English in class.
③One-third of the students in this class are girls.
④To swim in the river is a great pleasure.
⑤Smoking does harm to the health.
⑥The rich should help the poor.
⑦When we are going to have an English test has not been decided.
【答案】① country music (名词) ②We (代词) ③One-third (数词) ④To swim (不定式)
⑤ Smoking (动名词) ⑥The rich (名词化的形容词) ⑦ When we are going to have an English test (主语从句)
2.谓语
谓语说明主语所做的动作或具有的特征和状态。动词在句中作谓语,一般放在主语之后。谓语的构成如下:
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:(1)由情态动词或其他助动词加动词原形构成。如:
You may keep the book for two weeks. He has caught a bad cold.
(2)由系动词加表语构成。如:We are st