If a bag of sugar weighs 6 kilograms on earth, what will it weigh on the moon? It will weigh one kilogram on the moon, 1/6 of its weight on the earth.

Here on the earth we usually talks as if weight and mass were the same thing. We use weight as a way of measuring mass. On the earth this is very convenient. A mass of sugar that weighs 6 kilograms in California will weigh about 6 kilograms in Hawaii or Canada or Germany. Because the force of gravitation in each place is practically the same.

As long as we stay on earth, using weight to measure mass works pretty well. Now, however, men have left the earth. Suddenly we realize that weight and mass are not the same thing! Away from the earth the force of gravitation changes. As the pull gravitation changes, weight changes, but the mass of an object stays the same anywhere in the universe—whether it is on earth, on the moon, or on Mars.

Have you ever wondered why the pull of gravitation on the moon is only 1/6 of the pull on the earth? Here is a reason. When the mass is less, gravitation is less. The moon has less mass than the earth. Since the moon has much less mass than the earth, it has much less gravitational force than the earth.

1.Which of the following is NOT true?

A. Few people on the earth would pay much attention to the difference between weight and mass.

B.The weight of an object hardly changes wherever on the earth it is weighed.

C.The weight of an object becomes less on the moon because the moon is far away from the earth.

D.Mass is a concept(概念)more important than weight in the study of the universe.

2.The amount of mass depends on 　　  .

A. the weight of an object?　　　　　　　　　　　　　　 B.the place where it is measured

C.the size of an object?　　　　　　　　　　　　　　　　  D.the amount of matter it is made of

3.An astronaut, who weighed 30 pounds on the moon, is back on earth and now weighs 165 pounds. How much weight did he lose during his flight back to the earth?

A.115 pounds.　　　　　　   B.2.5 pounds.?　　　　    C.30 pounds.　　　　　　    D.15 pounds.

4.We can infer from the passage that the word “Mars” means 　　  .

A. a faraway place on the earth

B.a place deep down in the ocean

C.a kind of flying equipment like a spaceship

D.a planet which is farther away from the earth than the moon is

Remember what weight is? Weight is the gravitational pull on an object. If, somehow, the pull of gravitation changes, then the weight of the object changes. The mass of the object, the amount(数量)of matter it is made of, does not change.

If a bag of sugar weighs 6 kilograms on earth, what will it weigh on the moon? It will weigh one kilogram on the moon, 1/6 of its weight on the earth.

Here on the earth we usually talks as if weight and mass were the same thing. We use weight as a way of measuring mass. On the earth this is very convenient. A mass of sugar that weighs 6 kilograms in California will weigh about 6 kilograms in Hawaii or Canada or Germany. Because the force of gravitation in each place is practically the same.

As long as we stay on earth, using weight to measure mass works pretty well. Now, however, men have left the earth. Suddenly we realize that weight and mass are not the same thing! Away from the earth the force of gravitation changes. As the pull gravitation changes, weight changes, but the mass of an object stays the same anywhere in the universe—whether it is on earth, on the moon, or on Mars.

Have you ever wondered why the pull of gravitation on the moon is only 1/6 of the pull on the earth? Here is a reason. When the mass is less, gravitation is less. The moon has less mass than the earth. Since the moon has much less mass than the earth, it has much less gravitational force than the earth.

1.Which of the following is NOT true?

A. Few people on the earth would pay much attention to the difference between weight and mass.

B.The weight of an object hardly changes wherever on the earth it is weighed.

C.The weight of an object becomes less on the moon because the moon is far away from the earth.

D.Mass is a concept(概念)more important than weight in the study of the universe.

2.The amount of mass depends on 　　  .

A. the weight of an object?　　　　　　　　　　　　　　 B.the place where it is measured

C.the size of an object?　　　　　　　　　　　　　　　　  D.the amount of matter it is made of

3.An astronaut, who weighed 30 pounds on the moon, is back on earth and now weighs 165 pounds. How much weight did he lose during his flight back to the earth?

A.115 pounds.　　　　　　   B.2.5 pounds.?　　　　    C.30 pounds.　　　　　　    D.15 pounds.

4.We can infer from the passage that the word “Mars” means 　　  .

A. a faraway place on the earth

B.a place deep down in the ocean

C.a kind of flying equipment like a spaceship

D.a planet which is farther away from the earth than the moon is

书面表达

现在越来越多的人购买小汽车，请你根据下列表格所给信息

优点　　缺点　　建议

有了小汽车，能自由来去，不用花很多时间；小汽车对于旅行比较舒适；开小汽车比骑自行车安全。越来越多的小汽车会引起污染；引起交通拥挤和更多的交通事故。政府要适当控制小汽车的数量。

给报社编辑写一封信发表观点。假设你是中学教师张伟。字数：100左右。

　　Dear editor,

Yours,　　

Zhang Wei

If you visit a big city anywhere in the world,you will probably find a restaurant which serves the food of your native country.Most large 　1 in the United States offer an international sample of 　2 .Many people enjoy eating the food 　3 other nations.This is probably one reason 　4 there are so many different kinds of restaurants in the United States.A second is that Americans 　5 from all the parts of the world.They enjoy tasting the foods of their 　6 lands.

In the city of Detroit, 7 ,there are many people from Western Europe,Latin America 8 the Far East.There are many restaurants in Detroit 9 serve the foods of these areas.There are many

10 international restaurants,too.Americans not only like the foods in these restaurants but also enjoy the chance to 　11 understand the foreign people and their 　12 of life.

One of 　13 most common international restaurants to be 　14 in the US is an Italian restaurant.The restaurant is a small business 　15 by a single family.The mother of the 　16

cooks all the dishes and the 　17 and children serve the customers who come to eat there.Or it may be a 18 restaurant which can 　19 many customers during one evening.So a restaurant may be owned 　20 one family,one person,or by several different people who work together in the business.

1.A.cities　　　　　 B.countryside　　　 C.nations　　　　　 D.families

2.A.waiters　　　　 B.restaurants　　　 C.foods　　　　　　 D.cooks

3.A.about　　　　　 B.of　　　　　　　　 C.on　　　　　　　　 D.with

4.A.as　　　　　 B.when　　　　　 C.which　　　　　　 D.why

5.A.arrive　　　 B.come　　 　　　 C.go　　　　　　　　 D.leave

6.A.garden　　　 B.country　　　　　 C.state　　　　　　 D.native

7.A.as　　　　　 B.like　　　　　 C.for example　　　 D.such as

8.A.and　　　　　　 B.with　　　　　 C.of　　　　　　　　 D.then

9.A.where　　　 B.which　　　　　　 C.when　　　　　 D.why

10.A.other　　　 B.others　　　　　　 C.another　　　　　 D.other’s

11.A.worse　　　 B.better　　　　　　 C.hardly　　　　　　 D.more

12.A.hope　　　 B.wish　　　　　 C.place　　　　　　 D.way

13.A.the　　　　　　 B.a　　　　　　　 C.this　　　　　 D.that

14.A.cooked　　　　 B.enjoyed　　　　 C.found　　　　　　 D.eaten

15.A.built　　　 B.run　　　　　　 C.driven　　　　　　 D.lived

16.A.family　　　　 B.city　　　　　 C.business　　　 D.restaurant

17.A.mother　　　　 B.guests　　　　　　 C.visitors　　　　　 D.father

18.A.small　　　 B.large　　　　　　 C.tiny　　　　　 D.bad

19.A.deal　　　　　 B.work　　　　　 C.serve　　　　　　 D.prepare

20.A.by　　　　　　 B.with　　　　　 C.of　　　　　　　　 D.for