三、单词、短语和从句

1.单词（words）

句子的各成分在很多情况下均由单词表示，如：

（1）主语由名词或代词充当，有时也可由数词、动名词等充当：

We are proud of our country.

Three of us are going by boat.

Smoking is prohibited.

（2）谓语由动词或动词短语充当，有时由短语动词（phrasal verbs）充当：

We' ve been worrying about you.

We' d better take their advice.

I'll take care of him.

（3）表语可由名词、代词、形容词等充当：

The plan sounds great .

You look charming today.

（4）宾语常由名词或代词等充当：

Give me something to read.

How many do you want? I want two .

（5）定语常由形容词和代词（又称限定词determiners）或数词充当：

Los Angeles is the second largest city in the U.S.

Three people were injured in the accident.

2.短语（phrases）

可以担任句子成分的短语很多，常见的有：

（1）介词短语（prepositional phrases）：

We went swimming in the lake . （作状语）

He gazed at a portrait on the wall . （作定语）

She was in her early twenties . （作表语）

（2）不定式短语（infinitive phrases）：

To ignore this would be a mistake. （作主语）

Her wish was to become an artist . （作表语）

They love to listen to fairy tales . （作宾语）

It's time to go to bed . （作定语）

I'm sorry to hear it . （作状语）

He asked me to help him . （构成复合宾语）

（3）动名词短语（gerund phrases）：

I enjoy working with you . （作宾语）

Putting on airs is not welcome. （作主语）

Her major interest is collecting stamps . （作表语）

（4）现在分词短语（-ing participle phrases）：

There's a free way connecting the two cities . （作定语）

Sally was lying in bed thinking of her chil d . （作状语）

I found him dozing in class . （构成复合宾语）

（5）过去分词短语（-en participle phrases）：

Is there anything planned for tonight ? （作定语）

Moved by his sincerity , we accepted the gift. （作状语）

I felt a great weight taken off my mind . （构成复合宾语）

（6）名词短语（noun phrases）：

Thanks a lot . （作状语）

She bought a tube of toothpaste. （作定语）

（7）动词短语（verb phrases）：

I' ll be waiting for you at the gate. （作谓语）

Has anyone seen my glasses? （作谓语）

3.从句（clause）

从句是指一个有主语、谓语和句子相似的结构（也可称为主谓结构）。这种结构不是独立句子，而是构成句子的一个成分。从结构上看可分为五类：

（1）that 引起的从句（that 有时可以省略）：

He admitted that his motive was profit . （作宾语）

(That) You can ' t swim is a pity. （作主语）

The trouble with you is you won ' t listen . （作表语）

I'm glad you have come . （作状语）

（2）连接代词或副词及whether (if)引起的从句：

Do you know where they are ? （作宾语）

It hasn't been decided who is to be the prime minister . （作主语）

The question is how we could get their cooperation . （作表语）

He wasn't sure whether he ought to laugh or cry . （作状语）

（3）关系代词型的 what 引起的从句：

Show me what you have bought . （作宾语）

What you need is more practice. （作主语）

That's what I want to know . （作表语）

He began to think about what he should do . （作介词宾语）

（4）由各种连词引起的从句（多用作状语）：

Stay where you are .

Do as you please .

（5）关系从句（relative clauses)（由关系代词或副词引起的从句）常用作定语，因此也称作定语从句（attributive clauses）：

The girl who spoke is our monitor.

She was not in the train which （that) arrived just now . QYeWXIeOUAcmyfhFJR+dDSao4MJ443jed5toMp0nkDX5JVzKfurJmix4lbsSiQ4d