1. 连接子句与子句。如若干个句子在某方面有关连,常可用连接词连接成为一个含有若干个子句的句子,使原来句子之间的关系更紧密、自然。
Tom went to London yesterday. Jim went to London yesterday.
汤姆昨天去了伦敦。吉姆昨天去了伦敦。
连接上两句的方法:
Tom went to London yesterday, and Jim went to London yesterday.
Tom went to London yesterday, and so did Jim.

Mom, I was very busy last night, and so was my brother.
妈妈，我昨晚很忙，我兄弟也是。

2. 连接句中文法功能相同的部分。有时在两个分离的句子中,有某些部分用字相同而且文法作用也相同,只需将相同的保留其一,其余的省略,将句子成分相同而用字不同的部分用连接词连接起来,如连接主语与主语、动词与动词、宾语与宾语、补语与补语等。
Tom, as well as Jim, went to London yesterday.
Tom and Jim went to London yesterday.
汤姆和吉姆昨天去了伦敦。

Both Tom and Jim went to London yesterday.
汤姆和吉姆昨天都去了伦敦。

Not only Tom but also Jim went to London yesterday.
不但汤姆而且吉姆昨天也去了伦敦。
连接主语与主语。

He woke up and got out of bed.
他睡醒起床。
连接动词与动词。

I have neither time nor money.
我既没时间又没钱。
连接宾语与宾语。

He is not only a mean man, but a fool.
他不但是个卑鄙的人,而且是个蠢才。
连接主语补语与主语补语。

I saw them dancing and singing under a big tree.
我看见他们在一棵大树下跳舞、唱歌。
连接宾语补语与宾语补语。

Neither he nor I have to go to school.
他和我都不必上学。

3. 当连接两个动词片语时,如第二个动词片语里的助动词与第一个动词片语里的助动词相同时,应该省略助动词。
But we should not only be healthy, but also be in good shape.
我们不仅应该身体好，还要保持好的体型。

We should not only be bold, but also be cautious.
我们不仅要大胆,而且要谨慎。
but之后省略了助动词should。

4. 如果动词的形式相同,但功能不同时,不可省略。
I am your mother and am preparing breakfast for you.
我是你们的妈妈，我在为你们准备早餐。

He is a doctor and is doing an operation.
他是医生,现在正在做手术。
第一个is是联系动词"是",第二个is是助动词,二者功能不同,不可省略。

5. 如连接词若连接多个有to的不定词时,第一个to必须保留,其余的to可以省略。
Do you like to drink some tea? Do you like to have a cup of coffee?
连接以上两句的方法:
Do you like to drink some tea or have a cup of coffee?
你想要喝点茶还是来一杯咖啡?

6. 如果需用同一个连接词连接三个或三个以上的词语时,为避免重复,前面的连接词可用逗点代替,但最后两者之间要用连接词,该连接词之前的逗点可有可无。
Water, air, and sunshine are necessary to life.
水,空气和阳光是生命所必需的。

7. 连接两个子句只需一个连接词;同一个从属子句里不可有两个从属连接词,一个从属子句只能有一个从属连接词。
I asked him when he could finish his homework.
我问他何时能够写完功课。

8. 用连接词连接两个相同的字可以加强语气。
You two are getting lazier and lazier.
你们两个变得越来越懒了。

The weather is getting warmer and warmer.
天气变得越来越暖和了。