and的九大用法要点
1. 连接两个相同的比较级，表示“越来越……”。如：
It moves faster and faster. 它动得越来越快。
Your work is getting better and better. 你的工作干得越来越好了。
2. 连接两个相同的动词，表示动作的反复或连续。如：
He coughed and coughed. 他咳个不停。
He tried and tried but without success. 他试了又试，但没有成功。
3. 连接两个相同的名词，表示“许多”或“有各种各样的” (即有好的也有坏的)。如：
They talked for hours and hours. 他们谈了很长时间。
There are books and books. 有各种各样的书(即书有好坏之分)。
4. 在口语中用在 come, go, run, stay, stop, try 等之后表示目的(and 在此相当于不定式符号 to)。如：
Come and have a look. 来看一看。
We will try and get one tomorrow. 我们明天设法弄一个来。
We ought to stop and think. 我们应该停下来想一想。
Will you go and fetch me some paper, please? 请你去给我拿点纸来好吗?
以上动词除 try 只能用原形外，其它动词都可有多种形式。如：
正：We stayed and had a drink with him. 我们留下来同他喝 了一杯。
正：We stopped and bought some flowers. 我们停下来买了些 花。
误：He tried and finished the work in time.
注：在 come, go 之后的 and 有时可以省略(尤其在美国英语中)。如：
I’ll come (and) see you later. 我晚些时候再来看你。
5. 用在祈使句后，表示结果，意为“那么”(暗示一种条件)。如：
Work hard and you’ll pass the examinations (=If you work
hard, you’ll pass the examinations). 努力吧，你考试会及格的。
Arrive late once more and you’re fired (=If you arrivelate once more, you’re fired). 再迟到一次，就把你开除。
有时也可以不是用于祈使句后表示结果。如：
One more step and I will fire. 你再动一步，我就要开枪了。
6. 用在 good, nice, fine 等之后，表示“很”、“挺”。如：
It’s nice and cool under the tree. 这树下很凉快。
The book is nice and expensive. 这本书很贵。
7. 在主从复合句中，不要在主句前误加 and。如：
要是下雨，我们就呆在家里。
正：If it rains, we’ll stay at home.
误：If it rains, and we’ll stay at home.
8. 某些用 and 连接的两个词，与汉语顺序相反，不要按汉语词序颠倒过来。如：
rich and poor 贫富 land and water 水陆
right and left 左右 north and south 南北
food and drink 饮食 food and clothing 衣食
9. 比较以下各组句子有无连词 and 的差别：
天气晴朗，我们出去散了步。
正：The weather being fine, we went out for a walk.
正：The weather was fine, and we went out for a walk.
教室里包括老师有五个人。
正：In the classroom there are five people, the teacher included.
正：In the classroom there are five people, and the teacher was included.
他有两个小孩，都很顽皮(from www.hxen.com)。
正：He has two children, both of whom are naughty.
正：He has two children, and both of them are naughty.