题目内容
12．We can hardly believe such a young boy ______ travel around the world all by himself．（ ）| A． | may | B． | need | C． | should | D． | must |
分析 我们几乎无法相信这么小的孩子竟然独自环游世界．
解答 答案：C
解析：A：或许；可能；B：需要；C：竟然；D：必须．根据前面的"我们几乎无法相信"可知这么小的孩子"竟然"独自环游世界，故本题答案为C选项；其余选项均不符合题意．
点评 本题考查情态动词，做此类题目时一定要先分析各个选项的含义及其用法再结合句意选出正确答案．
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2．Third-generation mobile phones，known as 3G，are the next big step for the telecom industry．Data speed in 3G networks is much quicker than that in present technology．This means users can have high-speed Internet access and enjoy video and CD-quality music on their phones．
"Mobile data is not a dream； it's not an option but a requirement，"said Len Lauer，head of a U．S．Communications company，Sprint PCS，at a 3G conference in Bangkok earlier this month．
With 3G，you can forget about text messages telling you yesterday's news； a 3G phone can receive video news programs，updated four times a day．Internet access will also be much quicker，making it easier to surf the Web on your phone than on your computer at home．
Face-to-Face video calls
Don't worry about getting lost，3G phones offer map services so you can find a new restaurant just by pressing a few keys on your handset．
However，the most impressive part of 3G technology is video calling．With live two-way video communication，you can have face-to-face talks with friends and family on your mobile phone．
Many European countries have already launched the services．In May 2000the U．S．Government issued five license to run 3G wireless services，while the first 3G phones arrived in Italy in March this year．
International telecom companies can't wait to sell 3G in China，the world's largest mobile telecommunications market．But they will have to be patient．At the moment，China is busy testing its 3G-based technologies，networks and services．This will be followed by a trial period before the phones can finally hit the shops．
"We need to create a pool of 3G customers before the large-scale commercial launch of the service，"said Fan Yunjun，marketing manager for Beijing Mobile．"We expect that the 3G licences will be issued late next year．"
"Mobile data is not a dream； it's not an option but a requirement，"said Len Lauer，head of a U．S．Communications company，Sprint PCS，at a 3G conference in Bangkok earlier this month．
With 3G，you can forget about text messages telling you yesterday's news； a 3G phone can receive video news programs，updated four times a day．Internet access will also be much quicker，making it easier to surf the Web on your phone than on your computer at home．
Face-to-Face video calls
Don't worry about getting lost，3G phones offer map services so you can find a new restaurant just by pressing a few keys on your handset．
However，the most impressive part of 3G technology is video calling．With live two-way video communication，you can have face-to-face talks with friends and family on your mobile phone．
Many European countries have already launched the services．In May 2000the U．S．Government issued five license to run 3G wireless services，while the first 3G phones arrived in Italy in March this year．
International telecom companies can't wait to sell 3G in China，the world's largest mobile telecommunications market．But they will have to be patient．At the moment，China is busy testing its 3G-based technologies，networks and services．This will be followed by a trial period before the phones can finally hit the shops．
"We need to create a pool of 3G customers before the large-scale commercial launch of the service，"said Fan Yunjun，marketing manager for Beijing Mobile．"We expect that the 3G licences will be issued late next year．"
| Third-generation mobile phones （3G mobile phones） | |
| （71）Advantages | 14．Data speed：（72）quicker than presnet technology． 15．Video and （73）CD-quality music． 16．Video news programs：（74）updatedfour times a day． 17．Internet access：quicker and （75）easier． |
| Impressive functions | a．Offer（76）map services，helping you find way． b．Provide two-way video（77）communication． |
| 3G phones in China | a．China is busy（78）testingits 3G-based technologies，Networks and servies． b.3G phones should go through a （79）trialperiod Before being put into market． c.3G phones are expected to be seen （80）latenext year． |
3．Waste to Energy-JUST BURN IT!
WHY BURN WASTE？
Waste-to-energy plants generate （产生） enough electricity to supply 2.4million households in the US．But，providing electricity is not the major advantage of waste-to-energy plants．In fact，it costs more to generate electricity at a waste-to-energy plant than it does at a coal，nuclear，or hydropower plant．
The major advantage of burning waste is that it considerably reduces the amount of trash going to landfills．The average American produces more than 1，600pounds of waste a year．If all this waste were landfilled，it would take more than two cubic yards of landfill space．That's the volume of a box three feet long，three feet wide，and six feet high．If that waste were burned，the ashes would fit into a box three feet long，three feet wide，but only nine inches high!
Some communities in the Northeast may be running out of land for new landfills．And，since most people don't want landfills in their backyards，it has become more difficult to obtain permits to build new landfills．Taking the country as a whole，the United States has plenty of open space，of course，but it is expensive to transport garbage a long distance to put it into a landfill．
TO BURN OR NOT TO BURN？
Some people are concerned that burning garbage may harm the environment．Like coal plants，waste-to-energy plants produce air pollution when the fuel is burned to produce steam or electricity．Burning garbage releases the chemicals and substances found in the waste．Some chemicals can be a threat to people，the environment，or both，if they are not properly controlled．
Some critics of waste-to-energy plants are afraid that burning waste will hamper （妨碍，阻碍） recycling programs．If everyone sends their trash to a waste-to-energy plant，they say，there will be little motive to recycle．Several states have considered or are considering banning waste-to-energy plants unless recycling programs are in place．Massachusetts，New Jersey，and New York City have delayed new waste-to-energy plants，hoping to increase the level of recycling first．
So，what's the real story？Can recycling and burning waste coexist？At first glance，recycling and waste-to-energy seem to be at odds （不一致），but they can actually complement （弥补） each other．That's because it makes good sense to recycle some materials，and better sense to burn others．
Let's look at aluminum，for example．Aluminum mineral is so expensive to mine that recycling aluminum more than pays for itself．Burning it produces no energy．So clearly，aluminum is valuable to recycle and not useful to burn．
Paper，on the other hand，can either be burned or recycled-it all depends on the price the used paper will bring．
Plastics are another matter．Because plastics are made from petroleum and natural gas，they are excellent sources of energy for waste-to-energy plants．This is especially true since plastics are not as easy to recycle as steel，aluminum，or paper．Plastics almost always have to be hand sorted and making a product from recycled plastics may cost more than making it from new materials．
To burn or not to burn is not really the question．We should use both recycling and waste-to-energy as alternatives to landfilling．
Waste to Energy-JUST BURN IT!
WHY BURN WASTE？
Waste-to-energy plants generate （产生） enough electricity to supply 2.4million households in the US．But，providing electricity is not the major advantage of waste-to-energy plants．In fact，it costs more to generate electricity at a waste-to-energy plant than it does at a coal，nuclear，or hydropower plant．
The major advantage of burning waste is that it considerably reduces the amount of trash going to landfills．The average American produces more than 1，600pounds of waste a year．If all this waste were landfilled，it would take more than two cubic yards of landfill space．That's the volume of a box three feet long，three feet wide，and six feet high．If that waste were burned，the ashes would fit into a box three feet long，three feet wide，but only nine inches high!
Some communities in the Northeast may be running out of land for new landfills．And，since most people don't want landfills in their backyards，it has become more difficult to obtain permits to build new landfills．Taking the country as a whole，the United States has plenty of open space，of course，but it is expensive to transport garbage a long distance to put it into a landfill．
TO BURN OR NOT TO BURN？
Some people are concerned that burning garbage may harm the environment．Like coal plants，waste-to-energy plants produce air pollution when the fuel is burned to produce steam or electricity．Burning garbage releases the chemicals and substances found in the waste．Some chemicals can be a threat to people，the environment，or both，if they are not properly controlled．
Some critics of waste-to-energy plants are afraid that burning waste will hamper （妨碍，阻碍） recycling programs．If everyone sends their trash to a waste-to-energy plant，they say，there will be little motive to recycle．Several states have considered or are considering banning waste-to-energy plants unless recycling programs are in place．Massachusetts，New Jersey，and New York City have delayed new waste-to-energy plants，hoping to increase the level of recycling first．
So，what's the real story？Can recycling and burning waste coexist？At first glance，recycling and waste-to-energy seem to be at odds （不一致），but they can actually complement （弥补） each other．That's because it makes good sense to recycle some materials，and better sense to burn others．
Let's look at aluminum，for example．Aluminum mineral is so expensive to mine that recycling aluminum more than pays for itself．Burning it produces no energy．So clearly，aluminum is valuable to recycle and not useful to burn．
Paper，on the other hand，can either be burned or recycled-it all depends on the price the used paper will bring．
Plastics are another matter．Because plastics are made from petroleum and natural gas，they are excellent sources of energy for waste-to-energy plants．This is especially true since plastics are not as easy to recycle as steel，aluminum，or paper．Plastics almost always have to be hand sorted and making a product from recycled plastics may cost more than making it from new materials．
To burn or not to burn is not really the question．We should use both recycling and waste-to-energy as alternatives to landfilling．
Waste to Energy-JUST BURN IT!
| WHY BURN WASTE？ | Advantages of waste to Energy | ◆Though at a high （71）cost，waste-to-energy plants can produce enough electricity for 2.4million US households． ◆Burning waste can （72）reduce/prevent/stop a considerable amount of trash going to landfills． |
| （73）Difficulties for landfilling | ◆Some communities （74）lack land for new landfills． ◆Most people refuse to build landfills around． ◆Building landfills in far-away areas will increase the cost of （75）transporting garbage． | |
| TO BURN OR NOT TO BURN？ | （76）Concerns/Worries about burning garbage | ◆Burning garbage releases chemicals，which，if not properly controlled，can be （77）harmful/dangerous to people and the environment． ◆Burning garbage will hamper recycling programs． |
| Coexistence of recycling and burning waste | Recycling and waste-to-energy can go well with each other in that some materials like aluminum are fit to recycle，while others like plastics are fit to （78）burn． | |
| （79）Conclusion | Whether to burn or not to burn，we should （80）replace landfilling with both recycling and waste-to-energy to deal with garbage． | |
20．He commanded that the students ______the classroom before he returned．（ ）
| A． | didn't leave | B． | wouldn't leave | C． | not leave | D． | couldn't leave |
7．-Must I bring my lunch here？
-No，you__________．We have prepared it．（ ）
-No，you__________．We have prepared it．（ ）
| A． | shouldn't | B． | don't have to | C． | mustn't | D． | can't |
17．Don't feel guilty about it．Anyone _________make mistakes in their life．（ ）
| A． | can | B． | must | C． | shall | D． | need |
4．Scientists don't think that a warm winter always has a negative influence on our life，____？（ ）
| A． | don't they | B． | do they | C． | hasn't it | D． | has it |
1．You _______ call him if you want to，but you _______，for he'll surely come here soon．（ ）
| A． | may； mustn't | B． | can； needn't | ||
| C． | have to； needn't | D． | can； doesn't need |
2．-I'm afraid I can't find the key to the car．
-____，my dear．I'll wait for you．（ ）
-____，my dear．I'll wait for you．（ ）
| A． | Come on | B． | All right | C． | It is up to you | D． | Take your time |