a/an
[不定冠词]与单数名词连用
(1)在文中引出新的人或事件：An Englishman,a Scotsman and an Australian were on a plane...
(2)表示某人或某事是某个群体的一个成员：Fatima's a Muslim.
(3)泛泛地谈论一类事物： An octopus has eight legs.
注意：发音以辅音开头的单词前面用a,发音以元音开头的单词前面用an.
a plane;a Muslim; a house;a university student
an octopus; an hour;an umbrella;an MA
语法结构
1 名词短语 + is/was | + a/an | + 分类名词
My flatmate is a Swede.
Jane Austen was an English writer.
The kangaroo is a marsupial.
对人或事加以分类，比如说明其国籍或职业.
2 there | +is/was等 | + a/an | + 名词短语 | (+状语)
There is a supermarker next to the station.
There was an immediate reaction.
There was a strange smell in the kitchen.
(在描述时引出新话题)
3 名词短语| + has/'s got | + a/an | (+形容词) | + 名词短语
Milan has a Gothic cathedral.
Jan's got a nice smile.
Has vigo got an airport?
描述地点、人物和事物。
4名词短语 |+ is/was | + such | +a/an | + 名词短语
Kevin is such a hard worker.
It's such a shame.
强调对某事或某人的感受。
搭配
有很多用have a ...或take a ...开头的 “动词+名词”组合,例如:
have a drink,have a bite(to eat),have a laugh,have/take a look,have a go,have a talk,
have a say,have a try,have a ride,have/take a walk,have/take a rest.
Can you take a look at my homework?
We stopped at a roadside cafe and had a bite to eat.
I had a go on Robin's new motobike.
Everyone should have a say in the peace process.
固定用语
a few/a little/a lot (of) etc. 少数/少量/许多等
we had a few friends round for dinner.
There's a little salad left,if you'd like some.
How much time have we got? A lot.
谈论数量少数/少量/许多等.
a kilo/a metre/a dozen etc. 一千克/一米/一打等
Petrol costs 3 euros a litre.
How much are the eggs? F1.50 a dozen.
谈论价格.
a coffee/a fruit juice /a Coke etc .一杯/一瓶/一听咖啡/果汁/可乐等
Would you like a coffee?
He bought me a tomato juice and ordered a Scotch for himself.
指一杯/一瓶/一听某种饮料
a hundred/a thousand/a million etc.一百/一千/一百万等
A hundred and twenty people attended the meeting.
There were more than a million viewers
one 的非强调形式.
a year/a week /an hour etc.一年/一周/一个小时等
She checks her e-mail three of four times a day.
I go to the gym once a week.
They get paid less than ten dollars an hour.
谈论事情发生的频率或速率(这里a/an的意思是every,"每一个").