He used to be a medical student before he turned writer.
Child as he is, he knows a lot.
A man ran over, sword in hand.
7. 当man作“人类”、space作“太空”、nature作“自然界”、society 作“社会”、heaven作“天堂、天国”时不用冠词
8. 在称呼语前不加冠词。
Come in, boy. What are you doing, mum?
9. 在某些固定词组中
at home; write in pencil= write with a pencil
at daybreak/surprise/dawn/noon/dusk/sunset/sundown/night
day and night; day after day; day by day; hand in hand; side by side; from top to bottom; from beginning to end; from east to west; from morning till nigh
在一些短语中，有无冠词意义大不相同
by day在白天;by the day 按天计算
in case of 如果，万一;in the case of 就……来说
in charge of负责，管理;in the charge of 由……负责
go to church/school去作礼拜/去学习;go to the church/school到教堂去/学校去
out of question毫无疑问;out of the question不可能的
注：有些短语意义一样，但写法却不同。
On the whole= as a whole 大体上，就整体来看
take… for example= take … as an example 以……为例
不定冠词的用法：
1. 表示“一个”、“某一个”、“ 每一”、“再一，又一”、或“同一，相同”等
Eg. Rome is not built in a day.
A Mr. Smith is waiting for you at the school gate.
He usually works eight hours a day.
You can try it a second time if you fail.
They are of an age./ Birds of a feather flocks together.
2. 泛指某一类人或物，意为“任何一个，任一”
Eg: A square has four sides.
3. 当物质名词具体化表示“一(类、阵、份)”等;抽象名词具体化为“……的人或者事”时
Eg: Green tea is a wonderful tea.
We don’t have much rain here, but last night we had a heavy rain.
Reading is a pleasure for me.
The meeting is a great success.
4. 表示季节、月份、日期、三餐的名词，或表示世上独一无二的物体名词前有形容词修饰时
Eg: We have a every cold winter last year.
This happened on a rain Sunday towards the end of May.
We hope we can see a full moon tonight.
5. 源于动词的名词与take/have 连用时
Take a look; take a walk; have a break; have a visit to…
6. 用于某些固定词组中
All of a sudden; as a matter of fact; as a result; as a rule; as a whole; at a distance; in a way; in a hurry; in a sense; in a word; do sb. a favour; have a good time; have a word with ; go for a walk; make a difference; make a fool of oneself; make a living; pay a visit to ; take an interest in; tell a lie; a good/wise knowledge of; a danger/threat to sb.; come as a surprise/shock; wish sb. a Merry Christmas…
冠词的特殊位置
1. 不定冠词在感叹句中
What a lovely day it is! = How lovely a day it is!
2. 不到冠词与such, so, as, too连用
He is such a famous writer that…= He is so famous a writer that…
This is as difficult a problem as the one we met yesterday.
It’s too expensive a car for me to afford.
3. 不定冠词与half, many, quite, rather连用时
half a dozen of eggs; half an hour
many a teenager
quite a good idea/ rather a cold winter
注：an hour and a half, one and a half hours
4. 定冠词与all, both, half, double等连用
All the students feel they are under too much pressure.
Half the audience were bored with the movie.
I paid double the price.
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