阅读理解。

     Most American families like to have a vacation in summer. Summer is a good season for vacation. It is

often hot during the months of July and August. Children do not go to school during these two months.

     Some people like to stay at home during their vacation. They walk in the garden,visit their friends, read

books or watch TV. Many families take their lunch to a park or somewhere far from the city. They like to 

get where there are many trees or a nice lake. If they live near the ocean, they often go to the beach. There

they can fish,swim or enjoy the sun.

     Many Americans like to meet people from other countries like Mexico or Canada. Some people have

enough time and money to travel to other countries like Frence, Japan or Argentina. They usually fly to the

countries by plane. The United States is a large county. Many families travel by car or by train to see

interesting places in their country. Some favorite cities to visit are New York, Chicago, Miami, San Francisco

and Los Angeles. These big cities have many famous buildings, theaters, stores and other places of interest

for tourists.

     Not everyone likes to go to busy cities. Some families travel to the mountains or to beautiful valleys.

They usually take a camera and return with many nice pictures of the places they visit. It is always fun to

put the pictures in an album (相册) and share them with friends.

1. From the passage we know that children don't go to school during________.

A. the months of July and August

B. the months of June and July

C. the month of August and September

D. the month of July

2. Argentina is a ________.

A. city

B. village

C. country

D. town

3. Not everyone likes to go to busy cities. This sentence tells us that ________.

A. no one likes to go to busy cities

B. Everybody likes to go to busy cities

C. many people like to go to busy cities but not all like to go to

D. the United States is a large country indeed.

4. The underlined word "tourist" means "________".

A. 建筑师

B. 旅游者

C. 诗人

D. 商人

5. Which of the following is TRUE?

A. All the Americans like to meet people from other countries.

B. Americans like to travel to some mountains and valleys.

C. Americans really like to travel during their vacation.

D. If the people live near the ocean.they like to stay at home.

The central problem of economics is to satisfy the people’s and nation’s wants. The problem we are faced with is that our (1) , here identified as money, are (2) . The only way we can resolve our (3) is to make choices. After looking at our resources, we must examine our list of (4) and identify the things we need (5) , those we can postpone, and (6) we cannot afford. As individuals, we face the central problem involved in economics — deciding just how to allocate our limited resources to provide ourselves with the greatest (7) of our wants.
Nations face the same problem. As a country’s population (8) , the need for more goods and services grows (9) . Resources necessary to production may increase, but there are (10) enough resources to satisfy the total desires of a (11) . Whether the budget meeting is taking place in the family living-room, in the conference room of the corporation (12) of directors, or in the chamber of the House of Representatives in Washington, the basic problem still exists. We need to find (13) of allocating limited resources in order to satisfy unlimited wants.
A short time ago, economists divided goods into two categories, free and economic. The former, like air and water, were in (14) abundance that economists had no concern about (15) of scarcity and what to do about it. Today many of these "free goods" are in (16) very expensive to use. Pollution has made clean air and water expensive for producers who have to filter their waste products, for consumers who ultimately pay for the producers’ extra costs, and (17) tax-payers who pay for the government’s involvement in cleaning the environment.
In the 1990s, almost all goods are (18) . Only by effort and money can they be (19) in the form people wish.
Meeting the needs of people and the demands from resources available leads to the basic activity of production. In trying to (20) unlimited wants from limited economic goods, production leads to new problems in economics.