一、主语

基本概念 主语是一个句子所叙述的主体，表示句子说的是"什么人"或"什么事物"。 句中位置 陈述句中放在句首或谓语之前，但在there be结构、主语不含疑问词的疑问句和倒装句中，位于谓语、助动词或情态动词后面。 表现形式 名词(短语)、代词、数词、动词不定式(短语)、动名词(短语)、the＋形容词以及从句 典型例句 During the 1900s，American country music has become more and more popular.(名词)

We often speak English in class.(代词)

One­third of the students in this class are girls.(数词)

To swim in the river is a great pleasure.(不定式)

Smoking does harm to the health.(动名词)

The rich should help the poor.(名词化的形容词)

When we are going to have an English test has not been decided.(主语从句)

It is necessary to master a foreign language.(it作形式主语，真正的主语为后面的不定式) 　　二、谓语

基本概念 谓语说明主语的动作、特征或状态等。一般由动词担任，其人称和数必须与主语一致，有时态、语态和语气变化。 位置 一般在主语后(疑问句、倒装句除外)。 表现形式 动词(短语)、情态动词＋动词原形、某些动词＋不定式(如happen，would like，seen等)、系动词＋表语 典型例句 He has caught a cold.(动词)

You may keep the book for two weeks.(情态动词＋动词原形)

I would like to invite all my friends here.(其他动词＋不定式)

We are students.(系动词＋表语) 　　三、表语

基本概念 与系动词连用，一起构成复合谓语，说明主语的性质、特征、身份、类别、状态等。 句中位置 一般位于系动词(如be，become，get，look，seem，turn等)之后。 表现形式 名词、代词、数词、形容词、副词、不定式(短语)、动名词(短语)、分词、介词短语、从句 典型例句 Our teacher of English is an American.(名词)

Is it yours？(代词)

The weather has turned cold.(形容词)

The speech is exciting.(分词)

Three times seven is twenty one.(数词)

His job is to teach English.(不定式)

His hobby(爱好)is playing football.(动名词)

The machine must be out of order.(介词短语)

Time is up.The class is over.(副词)

The truth is that he has never been abroad.(表语从句)