题目内容
.They ______ be at home. You see, the door is locked from the outside.
A. can’t B. may C. must D. mustn’t
A
The central problem of economics is to satisfy the people's and nation's wants.
The problem we faced with is that our resources, here identified as money are __50__. The only way we can solve the problem is to make choices. After looking at our resources, we must examine our list of __51__ and identify the things we need immediately, those we can postpone, and __52__ we cannot afford. As individuals, we face the central problem involved in economics---deciding how to allocate(分配) our limited resources to provide __53__ with greatest satisfaction of our wants.
Nations face the same problem. As a country's population __54__, the need for more goods and services grows correspondingly. Resources necessary to production may increase, but there are __55__ enough resources to satisfy the total desires of a nation. Whether the budget meeting is taking place in the family living room, in the conference room of the corporation __56__ of directors, or in the chamber of the House of Representatives in Washington, the basic problem still exists. We need to find __57__ 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 __58__ abundance(丰富) that economists had no concern for them. After all, economics is the __59__ of scarcity and what to do about it. Today many of these "free goods" are __60__ very expensive to use. Population has made clean air and water expensive for producers extra cost, and __61__ taxpayers who pay for the government's involvement in cleaning the environment.
In the 1990s, almost all goods are __62__. Only by effort and money __63__ obtained in the from people wish.
Meeting needs of people and the demands from resource available __64__ the basic activity of production. In trying to meet unlimited wants from limited economic goods, production leads to new problems in economics.
| A. limited | B. unlimited | C. scarcity | D. abundant | |
| A. want | B. problem | C. wants | D. resources | |
| A. those | B. some | C. others | D. many | |
| A. them | B. themselves | C. ourselves | D. ours | |
| A. expand | B. extends | C. grows | D. increase | |
| A. always | B. sometimes | C. often | D. never | |
| A. management | B. function | C. board | D. group | |
| A. people | B. economists | C. way | D. methods | |
| A. so | B. great | C. such | D. such an | |
| A. form | B. study | C. means | D. source | |
| A. possibly | B. in practice | C. in fact | D. practically | |
| A. from | B. at | C. for | D. with | |
| A. plentiful | B. scarce | C. abundant | D. in full supply | |
| A. they can be | B. can they be | C. they must be | D. must they be | |
| A. are led to | B. leading to | C. lead to | D. leads to |