I .Articles(冠词)一下列情况只能用“a/an”1表示“一” There is a pen on the book.2第一次提到 He saw a wallet lying on the ground.3泛指 A boy can do it well.4表一类： A horse is useful.5惯用法 in a hurry6其他用法 a better job, a nicest boy a second time a hot Friday7不可数名词前有形容词修饰时： a big/heavy rain /snow; a big supper a great success 有一些不可数名词加了形容词后仍不能加不定冠词（weather news fun advice ,progress 等）8. 用在姓名、作品前，表示“具有特征的人”、“的作品”eg I wish to become an Edison. They have a Picasso in their living room.用在带姓的名字前，表示一位姓。的小姐或先生如：A Miss Chen came to see you this morning.9. 用在be +n+ of + a +n 的结构中表示不同事物的共同性。 Birds of a feather, cars of a kind二下列情况只能用“the”1第二次提到 Yesterday I saw a film. The film is directed by Zhang Yimou2表特指 Where have you put the key?3最高级 但 a strongest boy4序数级（单独用）the first, the last 但又一次：如a second5有后置定语修饰时（含从句）the science of life; the boy in the room the balance of nature 6独一无二的事物前 the sun the earth 但 a rising sun; a pale moon， in society in nature in space7表一类与一种的相同。The horse is useful. horses8乐器前 the piano the violin9固定搭配 in the morning the moment the minute10表示一类人的形容词前 the rich/poor/injured/wounded11表一家人 the Smiths12由普通名词组成的专有名词前 The Peoples Republic of China13沙漠、河流与群山，组织、党派和机关，书名杂志及报刊，定冠词不能删 the Tongting Lake ( Lake Tongting ), the United States, the Times14有后置定语修饰的地名/人名前加the (专有名词转化为普通名词) the China/ the Shaoxing of the twentieth century/ He is the Newton of the age.15. 对两人或两物进行比较时，起特定作用的比较级前 eg He is the taller of the two children.16.在发明物的单数前 the compass17. 及物动词+宾语+介词+the+ 身体的部位 catch him by the arm18. 用在历史朝代前 the Song Dynasty19. 在以sh/ch/ese/结尾的表示国家和民族的形容词前the，表示这个国家和民族的全体人员。 the French20.与表示计量单位的名词连用，含有“每” by the dozen/hour/ pound三下列情况既不用a 也不用the 1季节前，月份,星期，节假日前，in spring 但in the spring of 1989, in the year 20002表一类， Horses are useful.3棋类，球类 play Chinese chess4三餐前 但 a rich lunch5固定搭配 at once6学科前 English但 the English language7抽象名词前 但 the balance of nature the science of life8官衔，军衔前 he was made headmaster(补)但 Smith, the headmaster（同位语） is coming.9Turn 动词后， turn doctor10. as/though 前移的让步状语从句中。11在语言的名词前 如：English 但 the English language12在表示职位、职称、头衔的名词前Mr. Cook has been elected headmaster of the school.练习：1. Suzhou is compared to _ Venice of China.A. / B. a C. an D. the2. Yesterday was _ Childrens Day.A. a B. an C. / D. the3. Which do you think is _ of the two, Canada, or the USA?A. larger B. the larger C. largest D. the largest4. She said there was no _ thing.A. such a B. such C. a such D. so a 5. Tom owns _ larger collection of _ books than any other student in our class.A. the; / B. a; / C. a; the D. /; the6. The most important thing about cotton in history is _ part that it played in _ Industrial Revolution.A. /;/ B. the; / C. the; the D. a; the7. The wilsons live in _ A-shaped house near the coast. It is _ 17th century cottage.A. the; / B. an; the C. /; the D. an; a 8. For a long time they walked without saying _ word. Tim was the first to break _ silence.A. the; a B. a; the C. a; / D. the; /9. It is _ world of wonders, _ world where anything can happen.A. a; the B. a; a C. the; a D. /; /10. _ on-going division between English-speaking Canadians and French-speaking Canadians is _ major concern of country.A. The; / B. The; a C. An; the D. An; /11. - The news that he has been admitted to Beijing University is spreading from mouth to mouth.- Yes, its become _ talk of _ town.A. a; a B. the; / C. the; the D. a; /12. If you buy more than ten, they knock 20 pence off _.A. a price B. price C. the price D. prices13. While he was investigating ways to improve the telescope, Newton made _ discovery which completely changed _ mans understanding of color.A. a; / B. a; the C. /; the D. the; a 14. When you finish reading the book, you will have _ better understanding of _ life.A. a; the B. the; a C. /; the D. a; /15. Many _ astronaut wants to be _ second Yang Liwei.A. a; the B. an; a C. /; a D. a; a 16. Do you know _ art in the 18th century played _ more important part in peoples lives than it does today?A. an; the B. /; a C. the; a D. the; the17. Do you know _ speaker of _ Chinese language also has difficulty in learning Japanese?A. the; the B. a; the C. /; the D. the; /