- 单选题Many scientists have been probing psychological problems.
- 单选题Many diseases can be cured by orthodx medical treatment.
- 单选题He will consolidate his power.
- 单选题In World War II,the Soviet government allocated important resources.
- 单选题The conference wash hailed as a great success.
- 单选题The letter without the address puzzled me.
- 单选题We often take a stroll in the park after dinner for about an hour.
- 单选题共用题干 Obtaining Drinking Water from Air Humidity<br><br>Not a plant to be seen,the desert ground is too dry.But the air contains water,and research scientists<br>have found a. __________<br>(51)of obtaining drinking water from air humidity."The process we have <br>developed is based exclusively on renewable energy sources_________(52)thermal solar collectors and<br>photovoltaic（光电的）cells , ________( 53 ) makes this method completely energy-autonomous. It will <br>____________( 54 ) function in regions where there is no electrical infrastructure（基础设施）,"says Siegfried <br>Egner,head of the research team. The principle of the_________(55)is as follows:hygroscopic（吸湿的） <br>brine（盐水）一saline（含盐的）solution which absorbs moisture一runs down a tower-shaped unit and absorbs <br>water from the air. It is then sucked__________(56)a tank a few meters off the ground in which a vacuum <br>prevails.Energy from solar collectors_________(57)up the brine,which is diluted by the water it has<br>__________ (58).<br>Because of the vacuum,the boiling point of the liquid is lower than it would be under__________(59) <br>atmospheric pressure. The evaporated (蒸发的）, non-saline water is condensed and runs down through a <br>completely filled tube in a controlled manner. The gravity of this water column_______(60)produces the <br>vacuum and so a vacuum pump is not needed.The reconcentrated brine________(61)down the tower <br>surface again to absorb moisture from the air.<br>"The concept is suitable for various water________(62).Single一person units and plants<br>supplying water to entire hotels are conceivable,"says Egner. Prototypes have been built for_______<br>(63)system components一air moisture absorption and vacuum evaporation一and the research scientists<br>have already __________(64)their interplay on a laboratory scale.In a further ________(65)the re- <br>searchers intend to develop a demonstration facility.
- 单选题He was weary of the constant battle between them.
- 单选题The agreement was terminated immediately.
- 单选题That uniform makes the guards look absurd．
- 单选题He has been granted asylum in France.
- 单选题I answered the letter yesterday.
- 单选题The tower remains intact even after two hundred years.
- 单选题Growing levels of pollution represent a serious health hazard to the local population.
- 单选题A great deal has been done to remedy the situation.
- 单选题The decision to invade provoked swarms of protest.
- 单选题It was a magic night until the spell was broken.
- 单选题The country is abundant in natural resources.
- 单选题共用题干 American Families<br>1 Despite social and economic differences among Americans,many American families have certain characteristics in common.Both the husband and wife were born in the United States,and their forefathers came from Europe.They have completed high school,and they belong to the middle class.They have a car, a television set,a washing machine,a refrigerator,a telephone,etc.They own their own home and spend about 55%of their income for housing and food.Clothing accounts for almost 10%of their income,medical care 6%,transportation 8%and taxes 15%.The rest of their income is used for such items as insurance, savings,gifts,and recreation.<br>2 Most families consist of a mother,a father,and,at most,two children living at home.There may be relatives-grandparents,aunts,uncles,cousins living in the same community,but American families usually maintain separate households.This family structure is known as the"nuclear family".It is unusual. for members of the family other than the husband,wife,and children to live together.<br>3 Marriage in the United States is considered a matte,r of individual responsibility and decision.Young people frequently fall in love and many even if their parents disagree.American marriages are usually based on romantic love,rather than on social class,education,or religion.<br>4 After their marriage the young couple is free to decide where to live and when to start a family.Most young couples set up their own household immediately.In the early 1970s only 15%of all married couples were not living on their own-independently and by themselves.Most married people practise some kind of birth control.They plan the number of children they are going to have and when their children will be born. The practice of limiting the size of families has general approval.The birth rate has been declining steadily in recent years.
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