题目内容

54
A improves
B moves
C falls
D rises

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55 A in B for C at D of

下面有3篇短文，每篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。
第一篇
The Hyper-X
The Hyper-X（超音速飞机）recently broke the record for air-breathing jet planes when it traveled at a Hypersonic speed（超音速）of seven times the speed of sound．That's about 5,000 miles per hour．At this speed，you'd get around the world-flying along the equator （赤道）-in less than 5 hours．
The Hyper-X is an unmanned，experimental aircraft just 12 feet long．It achieves hypersonic speed using a special sort of engine known as a scramjet（超音速冲压式喷气发动机）．
For an engine to burn fuel and produce energy，it needs oxygen．A jet engine，like those on passenger airplanes，gets oxygen from the air．A rocket engine typically goes faster but has to carry its own supply of oxygen．A scramjet engine goes as fast as a rocket，but it doesn't have to carry its own oxygen supply．
A scramjet's special design allows it to obtain oxygen from the air that flows through the engine．And it does so without letting the fast-moving air put out the combustion（燃烧） flames．However，a scramjet engine works properly only at speeds greater than five times the speed of sound．
A booster rocket（助推火箭）carried the Hyper-X to an altitude of about l00，000 feet for its test flight．The aircraft's record-beating flight lasted just 11 seconds；That brief journey on March 27 makes a major milestone on the way to a new breed of very fast airplanes, says Werner J．A．Dahm of the University of Michigan in Ann Arbor．In the future，engineers Predict，airplanes equipped with scramjet engines could transport cargo quickly and cheaply to the brink（边缘）of space．Such hypersonic jets could carry passengers anywhere in the world in just a few hours．
Out of the three experimental Hyper．X aircrafts built for NASA, only one is now left．The agency has plans for another 11-second hypersonic flight, this time at 10 times the speed of sound．
31 The Hyper-X broke the record because
A it was the first air-breathing jet plane．
B it flew along the equator．
C it traveled at the speed of sound．
D it reached a speed of about 5, 000 miles per hour，

44 The word "fraction" in the second paragraph means
A a very small amount.
B a large area.
C an important system.
D a major source of information.

第三篇
Youth Emancipation in Spain
The Spanish Government is so worried about the number of young adults still living with their parents that it has decided to help them leave the nest.
Around 55 percent of people aged 18-34 in Spain still sleep in their parents' homes,says the latest report from the country's state-run Institute of Youth.
To coax (劝诱) young people from their homes, the Institute started a "Youth
Emancipation (解放)" program this month. The program offers guidance in finding rooms and jobs.
Economists blame young people's family dependence on the precarious (不稳定的) labor market and increasing housing prices. Housing prices have risen 17 percent a year since 2000.
Cultural reasons also contribute to the problem, say sociologists (社会学家). Family ties in south Europe - Italy, Portugal and Greece - are stronger than those in middle and north Europe, said Spanish sociologist Almudena Moreno Minguez in her report "The Late Emancipation of Spanish Youth: Key for Understanding".
"In general, young people in Spain firmly believe in the family as the main body around which their private life is organized," said Minguez.
In Spain - especially in the countryside, it is not uncommon to find entire groups of aunts, uncles, cousins, nieces and nephews (外侄/侄子) all living on the same street. They regularly get together for Sunday dinner.
Parents' tolerance is another factor. Spanish parents accept late-night partying and are wary of setting bedtime rules.
"A child can arrive home at whatever time he wants. If parents complain he'll put up a fight and call the father a fascist," said Jose Antonio Gomez Yanez, a sociologist at Carlos III University in Madrid.
Mothers' willingness to do children's household chores (家务) worsens the problem. Dionisio Masso, a 60-year-old in Madrid, has three children in their 20s. The eldest, 28, has a girlfriend and a job. But life with mum is good.
"His mum does the wash and cooks for him: in the end. he lives well." Masso said.
41 The "Youth Emancipation" program aims at helping young people
A fight for freedom.
B live in an independent way.
C fight against social injustice.
D get rid of family responsibilities