He is the teacher we talked about yesterday。
An island, a small island, an honest man, a house, a university, 还应注意
He is a European. I got a one hundred.
可数名词单数 The book A book A book
可名词复数 The books Books Some/any books
不可数名词 The water Water some/any water
1．不定冠词表示"一"这个数量的时候，意思和one差不多。但one更侧重"数目"这一概念，如yesterday I bought one book, not two. 通常表示重量，长度，时间等词组。
The apples are two yuan a pound.
Give me a cup of tea. Twice a week, eight hours a day...
I have a good idea. I have good news.
At that time I was working in a factory.
A young man wanted to see you.
A dictionary is a book.
Do you have a pen?
There is a man standing in front of the bank.
I met a friend of yours yesterday.
Yesterday I saw a dog. The dog was running after a cat. The cat ran into a hole. The hole was very small.
There was a king. The king had a man. The man could make gold out of stone.
Do you want to hear a story about an American, a German and a Polish.
He will give you information about hotels.
This house is made of wood.
Open the door please.
We will go to the market to buy some CDs.
The earth moves round the sun once a year.
当表示世界上独一无二的东西时，sun, moon, earth, world, air, stars (星系)，应加上the.
The rich are not always happy
Most of the books on the table are novels.
He is the doctor whom I told you of yesterday.
This is the city in which I live.
I live in a city far away from here. (听者不知道)。
You can ask the woman in front of you.
I saw a woman looking like your mother. (听者不知道是谁)
The ball hit his eye. = The ball hit him i