17.表示存在的問題
　　1)One of the greatest problems facing the 21st century will be what to do with all the rubbish produced in the world.
　　2) The frequent use of drugs (毒品) is a serious problem among some American young people.
　　3) To travel abroad is a desire shared by many people, but few can afford to do it.
　　 4) Man still has a lot to learn about the most powerful and complex part of his body-the brain.
　　5) We had a ling debate as to whether we should spend so much money on space technology.
　　6) Many people have the bad habit of spending money on impulse.
　　7) The custom of having one’s marriage arranged by parents has disappeared in many parts of the world but continues in some Asian and African countries.
　　8) Cheating is now considered to be a major problem in colleges and universities.
　　9) No agreement was reached as to how the plan should be carried out.
　　10) True, the cost of living has gone up, but so have the workers ‘wages.
　　11) I had trouble learning or doing something important to me.
　　12) She had a little trouble with her typing.
　　13) Many university students experience severe tension (緊張) as final exams draw near.
　　14) Until recently this hostile (敵對(duì)的) attitude towards daydreaming was the most common one .
　　15) Many people find it harder and harder to keep up with the radical changes that characterize our time.
　　16) If this project is to be carried out, we must have all the help that modern technology can supply.
　　17) When the days seem to go by slowly, you can tell that you’re not enjoying yourself.
　　18) Large amounts of food imports placed a great strain(負(fù)擔(dān)) on the country’s gold reserve(黃金儲(chǔ)備)
　　19)Corruption(腐敗) in government is not tolerated in any country that wants to achieves rapid economic growth and improve the life of its citizens.
　　20) At first thought, the problem seems far too involved (復(fù)雜) , but it can certainly be solved when seriously dealt with .
　　21) Colleges are not always adjusted to the needs of society to they need reform from time to time.
　　22) We’re all used to thinking that work provides the material things of life.
　　18. 表示可能性
　　1)If I wasn’t able to avoid a mistake, chances were that no other surgeon could have, either.
　　2) I think it is very unlikely that he will get the job; however, it may be worth a try.
　　3) I feel sure that if I had come from a different background, and had really been unemployed, there is every chance that I would have been found guilty (有罪).
　　4) If you try to pass the problems by, it would be impossible for you to make any progress in this field.
　　5) Then you might as well (完全可以) make a little money from them.
　　6) If the right kind of extracurricular (課外的) activities are organized, those children who have a surplus of energy(學(xué)有余力) will have a chance to develop their talents much more quickly.
　　7) It was almost impossible for an Indian to gain even a fair education an extremely difficult, as a result, for an Indian to rise high in life.
　　8) However carefully restricted the upward trips might be ,the chances are that the dwellers(居民) of the new caves would see more greenery than dwellers of surface cities do today .
　　19.表示決心或信心
　　1)We never lose heart when we meet with difficulties in our work.
　　2) Colleges and universities across the nation have decided to do more than talk about the rise in student cheating.
　　3) Nothing can stand in the way of the Chinese people in their resolve (決心) to modernize their country.
　　5) Anyway (不管怎樣) ,don’t give up . You could do it if you really resolve to do it.
　　6) Those animal protectors claimed solemnly(嚴(yán)肅的) that they would spare no efforts¬(不遺余力地) to carry the struggle through to the end.
　　20. 表示建議
　　1) I would like to propose that from sixty to ninety minutes each evening all television broadcasting in the United States be prohibited by law.
　　2) You should take advantage of this opportunity and try to make good impression on them.
　　3) Neither believe nor reject anything because any other person has rejected or believed it.
　　4) Greater efforts are needed before we can attain our goal of economic reform.
　　5) A country should protect its natural resources by fighting against waste.
　　6) Sometimes even an one-day vacation from work is enough to allow us to regain our strength and return to work fit and ready to do a better job.
　　7) If we concentrate our efforts on improving quality, our products will certainly be more competitive on the world market.