题目内容
17．-Whose notebook is this？-It ______ be Nacy's．It has her name on it．（ ）
| A． | need | B． | can't | C． | must | D． | shall |
分析 --这是谁的笔记本？
--它肯定是纳西的．它上面有她的名字．
解答 答案：C．考查情态动词．need需要．can't不能．must肯定，必须．shall应该．根据It has her name on it它上面有她的名字，可知，肯定是纳西的，用must．答案是C．其它不符合．
点评 情态动词无人称和数的变化；不能单独使用，必须与其后的动词原形构成谓语．否定形式通常在后面加not．要注意情态动词的不同用法．
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7．-Which robot do you think is the most useful？
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-_____________．（ ）
| A． | The robot that are made in Japan | |
| B． | The robot is designed to help us with our homework | |
| C． | The robot has a lot of memory | |
| D． | The robot shown at the exhibition centre |
8．-Don't play with fire．It's very dangerous!
- ．（ ）
- ．（ ）
| A． | Never mind． | B． | All right． | ||
| C． | That's all right． | D． | You're welcome． |
12．I'm not sure，but he's supposed sometime next week．（ ）
| A． | return | B． | returns | C． | to return | D． | returning |
5．In the past，man did not have to think about the protection of his environment．There were not many people on earth，and natural resources seemed to be unlimited．
Today，things are different．The world has become too crowded．We are using up our natural resources too quickly，and at the same time we are polluting our environment with dangerous chemicals．If we continue like this，human life on earth will not survive．
Everyone realizes today that if too many fish are taken from the sea，there will soon be none left．Yet，with modern fishing methods（方法），more and more fish are caught．We know that if too many trees are cut down，forests will disappear and nothing will grow on the land．Yet，we continue to use bigger and more powerful machines to cut down more and more trees．
We realize that if rivers are polluted with waste products from factories，we will die．However，in most countries waste products are still put into rivers or into the sea，and there are few laws to stop this．
We know，too，that if the population of the world continues to rise at the present rate，in a few years，there will not be enough food．
What can we do to solve these problems？
If we eat more vegetables and less meat，we will easily get more food．Land that is used to grow crops can feed five times more people than land where animals are kept．
The world population will not rise so quickly if people use modern methods of birth control．
Finally，if we educate people to think about the problems，we shall have a better and cleaner living place in the future．
Today，things are different．The world has become too crowded．We are using up our natural resources too quickly，and at the same time we are polluting our environment with dangerous chemicals．If we continue like this，human life on earth will not survive．
Everyone realizes today that if too many fish are taken from the sea，there will soon be none left．Yet，with modern fishing methods（方法），more and more fish are caught．We know that if too many trees are cut down，forests will disappear and nothing will grow on the land．Yet，we continue to use bigger and more powerful machines to cut down more and more trees．
We realize that if rivers are polluted with waste products from factories，we will die．However，in most countries waste products are still put into rivers or into the sea，and there are few laws to stop this．
We know，too，that if the population of the world continues to rise at the present rate，in a few years，there will not be enough food．
What can we do to solve these problems？
If we eat more vegetables and less meat，we will easily get more food．Land that is used to grow crops can feed five times more people than land where animals are kept．
The world population will not rise so quickly if people use modern methods of birth control．
Finally，if we educate people to think about the problems，we shall have a better and cleaner living place in the future．
| The importance of （46）protecting the environment | |
| Problems | ◆More fish are caught． ◆More （47）trees are cut down． ◆Waste products are still （48）put into rivers． ◆The population of the world keeps （49）rising at present． |
| Causes | ◆The world is becoming too（50）crowded． ◆Modern methods make the situation （51）worse． |
| （52）Result | We human beings will not survive on the earth． |
| Solutions | ◆Eat more vegetables and less meat so that more food will be provided for everyone，because there will be more （53）landto grow crops． ◆Use modern methods of（54）birth control so that the population will not grow too fast． ◆（55）Educatepeople so that the earth will be better and cleaner． |