1. 連接子句與子句。如若干個句子在某方面有關連,常可用連接詞連接成為一個含有若干個子句的句子,使原來句子之間的關系更緊密、自然。
Tom went to London yesterday. Jim went to London yesterday.
湯姆昨天去了倫敦。吉姆昨天去了倫敦。
連接上兩句的方法:
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.
媽媽，我昨晚很忙，我兄弟也是。

2. 連接句中文法功能相同的部分。有時在兩個分離的句子中,有某些部分用字相同而且文法作用也相同,只需將相同的保留其一,其余的省略,將句子成分相同而用字不同的部分用連接詞連接起來,如連接主語與主語、動詞與動詞、賓語與賓語、補語與補語等。
Tom, as well as Jim, went to London yesterday.
Tom and Jim went to London yesterday.
湯姆和吉姆昨天去了倫敦。

Both Tom and Jim went to London yesterday.
湯姆和吉姆昨天都去了倫敦。

Not only Tom but also Jim went to London yesterday.
不但湯姆而且吉姆昨天也去了倫敦。
連接主語與主語。

He woke up and got out of bed.
他睡醒起床。
連接動詞與動詞。

I have neither time nor money.
我既沒時間又沒錢。
連接賓語與賓語。

He is not only a mean man, but a fool.
他不但是個卑鄙的人,而且是個蠢才。
連接主語補語與主語補語。

I saw them dancing and singing under a big tree.
我看見他們在一棵大樹下跳舞、唱歌。
連接賓語補語與賓語補語。

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

3. 當連接兩個動詞片語時,如第二個動詞片語里的助動詞與第一個動詞片語里的助動詞相同時,應該省略助動詞。
But we should not only be healthy, but also be in good shape.
我們不僅應該身體好，還要保持好的體型。

We should not only be bold, but also be cautious.
我們不僅要大膽,而且要謹慎。
but之后省略了助動詞should。

4. 如果動詞的形式相同,但功能不同時,不可省略。
I am your mother and am preparing breakfast for you.
我是你們的媽媽，我在為你們準備早餐。

He is a doctor and is doing an operation.
他是醫生,現在正在做手術。
第一個is是聯系動詞"是",第二個is是助動詞,二者功能不同,不可省略。

5. 如連接詞若連接多個有to的不定詞時,第一個to必須保留,其余的to可以省略。
Do you like to drink some tea? Do you like to have a cup of coffee?
連接以上兩句的方法:
Do you like to drink some tea or have a cup of coffee?
你想要喝點茶還是來一杯咖啡?

6. 如果需用同一個連接詞連接三個或三個以上的詞語時,為避免重復,前面的連接詞可用逗點代替,但最后兩者之間要用連接詞,該連接詞之前的逗點可有可無。
Water, air, and sunshine are necessary to life.
水,空氣和陽光是生命所必需的。

7. 連接兩個子句只需一個連接詞;同一個從屬子句里不可有兩個從屬連接詞,一個從屬子句只能有一個從屬連接詞。
I asked him when he could finish his homework.
我問他何時能夠寫完功課。

8. 用連接詞連接兩個相同的字可以加強語氣。
You two are getting lazier and lazier.
你們兩個變得越來越懶了。

The weather is getting warmer and warmer.
天氣變得越來越暖和了。