题目内容
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Purging air from a hydraulic system is necessary when .
A.adding small amounts of oil to the system
B.the system has been overheated
C.the system has been drained and then filled with new oil
D.the system has been idle for a long period of time
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更多“Purging air from a hydraulic system is necessary when .A.adding small amounts of oil to th”相关的问题
The purging of air from an elector-hydraulic steering gear unit is necessary when .
A.changing over to hand pump operation
B.engaging the trick wheel
C.the system has been filled with new oil
D.the rudder angle indicator does not match the helm position
Which of the following CANNOT be inferred from the passage？
A．In a more productive world, hay fever sufferer will have an even more difficult time.
B．Cigarette smoker will stiffer more from heart and lung disease with the world becoming warner.
C．Tropical disease might spread to Europe and U.S.
D．CO2 level in the air has effect on the climate.
What can we learn about the millennial generation from the last paragraph？
A.It’s much more flexible than previous generations in social life。
B.It has higher expectation for balance than previous generations．
C.It tends to seek for more opportunities than．previous generations．
D.It’s braver in purging what they want than previous generations．
Section A
Directions: In this section, there is a passage with ten blanks. You are required to select one word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item with a single line through the center. You may not use any of the words in the bank more than once.
Air Pollution refers to the addition of harmful substances to the atmosphere resulting in damage to the environment, human health, and【S1】______of life. One of many forms of pollution, air pollution occurs inside homes, schools, and offices; in cities; across continents; and even【S2】______. Air pollution makes people sick—it causes breathing problems and【S3】______cancer—and it harms plants, animals, and the ecosystems (生态系统) in which they live. Some air pollutants return to earth in the form. of acid rain and snow, which destroy【S4】______and buildings, damage crops and forests, and make lakes and streams【S5】______for fish and other plant and animal life.
Pollution is changing Earth's atmosphere so that it lets in more harmful radiation from the Sun. At the same time, our polluted atmosphere is becoming a better insulator (绝缘体), which can【S6】______heat from escaping back into space and lead to a rise in global average temperatures. Scientists【S7】______that the temperature increase, referred to as global warming, will affect world food supply, alter sea level, make weather more【S8】______, and increase the spread of tropical disease.
Although the effects of future【S9】______change are unknown, some report that exaggerated weather conditions may【S10】______affect agriculture, for example, it may lead to severe drought and sharply decreasing agricultural yields in parts of Africa.
A) globally B) promotes C) predict D) unsuitable
E) science F) dramatically G) protect H) prevent
I) quality J) climate K) statues L) significant
M) powerful N) moderately O) extreme
【S1】
Starving Oneself
2 Anorexia nervosa is an eating disorder in which people starve themselves. Anorexics have an irrational fear of becoming fat and see themselves as much heavier than they really are. They shun food and may exercise for hours every day in an attempt to lose weight.
3 Female anorexics may never mature sexually or may stop menstruating because they lose too much body fat, causing the level of sex hormones to fall. Their body temperature and pulse rate become abnormally low; their hair becomes thin and dry; and their resistance to infection drops.
Bingeing and Purging
4 Patients with bulimia engage in frequent episodes of bingeing (eating a large amount of food in a short time). After a binge, they almost always purge by self-induced vomiting or by using laxatives. Therefore, their weight stays fairly constant. Unlike anorexic patients, bulimics often recognize that their behavior. is abnormal and often feel guilty, depressed, and helpless.
5 The frequent purging removes salts from the body, which can eventually lead to muscle weakness, heart failure, and kidney disease. The vomiting gradually destroys tooth enamel and results in unhealthy gums.
Help for People with Eating Disorders
6 Little is known about what causes anorexia nervosa and bulimia. Many people believe that western society's emphasis on thinness in women is largely to blame. However, recent research suggests that genetic factors might also be involved. Both eating disorders can be managed with a combination of medical treatment, counseling, and family support.
What may be the influence of anorexia on female？
A．muscle weakness and heart failure
B．kidney disease and low body temperature and pulse rate
C．dropping resistance to infection
D．destroyed tooth enamel and unhealthy gums
(see) ______from the air, the island is a sleeping girl.
The engine is started with () supplied from air receivers.
A.pressure oil
B.compressed air
C.pressure water
A、formed
B、forming
C、form
D、and forming
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