pair用法如下：
1、pair做为名词，表示一双；一对；后接表示相同的两样东西，习惯上一起使用的名词。
a pair of socks一双袜子
a pair of gloves一副手套
a pair of shoes一双鞋
a pair of earrings一对耳环
a pair of chopsticks一双筷子
The vase is one of a matching pair. 这只花瓶是一对中的一只。
2、pair做名词，表示由两部分构成的单件事物。
a pair of trousers/pants/jeans一条长裤、裤子、牛仔裤
a pair of scissors一把剪刀
a pair of glasses一副眼镜
a pair of binoculars一架双筒望远镜
I cut the paper with a pair of scissors.
我用剪刀剪纸。
Two pairs of your trousers are still at the cleaner’s.
你的两条裤子还在洗衣店里。
对于这类由两部分构成的单件事物，我们不能用one或ones来替代它，而用pair或pairs。
这些裤子我穿太紧了，你有宽一点的吗?
误：These trousers are too tight for me. Do you have a larger one?
正：These trousers are too tight for me. Do you have a larger pair?
3、pair做名词，表示身体中两个相同的部位。
a huge pair of eyes一双大眼晴
She has a huge pair of eyes.
她长有一双大眼睛。
Look at her beautiful pair of legs.
你瞧她那又美丽的大腿。
4、pair做名词，表示表示一般意义的“两个”“一对”。
On the wall were a pair of hearts interlocked.
墙上有一个同心结。
A pair of thieves were conspiring to rob us.
有两个贼预谋盗窃我们的东西。
A pair of teenage boys were smoking cigarettes.
两个十来岁的男孩正在吸烟。
5、pair做名词，表示夫妻。
The pair are looking for sponsorship from local businesses.
这对夫妇正在寻求当地企业的赞助。
That pair are always quarreling.
那对夫妻老是争吵。