单项选择题
下列短文中有十个空白,每个空白有四个选项。根据上下文要求选出最佳答案。
The basic principle of radar is illustrated by what happens when one shouts in a cave. The echo of the shouting (11) the walls helps a person determine the size of the cave. With radar,however,the waves are radio waves instead of (12) waves. Radio waves travel (13) the speed of light,about300,000 kilometers in a second. A radar set (14) a short burst of radio waves. Then it receives the echoes (15) when the waves bounce(反射)off objects. By determining the time it (16) for the echoes to return to the radar set,a trained technician (17) determine the distance between the radar set and other objects. The word“radar”, (18) ,gets its name from the term“radio detection and ranging. ”“Ranging”is the term for detection of the (19) between an object and the radar set.
Besides being of critical importance to pilot,radar is (20) for air traffic control,for tracking ships at sea,and for tracking weather systems and storms.

A.in
B.at
C.over
D.on


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2.单项选择题
从下列每篇短文的问题后所给的四个选择项中选出一个最佳答案。
Passage One
Questions 21 to 25 are based on the following passage.
Among the company was a lawyer,a young man of about twenty-five. On being asked his opinion,he said,“Capital punishment and life imprisonment are equally immoral. If I were to make a choice between them,I would rather choose the latter. Anyway,it’s better to live than not to live at all. ”
A lively discussion followed. A banker,who was then younger and more nervous than the lawyer,suddenly lost his temper and cried out,“It’s a lie. I bet you two millions. You wouldn’t stick in a cell even for five years. ”
“If you mean it,”replied the young lawyer,“I bet I’ll stay there longer;make it fifteen instead of five. ”
“Fifteen!Done!”cried the banker. “Gentleman. I bet you two millions. ”
“Agreed. Two millions for my freedom,”said the lawyer.
So this wild,ridiculous bet came to pass. The banker could not hide his excitement. During supper he said to the lawyer jokingly,“Come to your senses,young man,before it’s too late. Two millions are nothing to me,but you stand to lose three or four of the best years of your life. I say three or four because you’ll never stick it out any longer. Don’t forget that voluntary imprisonment is much harder to put up with than an enforced one. The idea that you have the right to free yourself any moment will poison your life in the cell. I pity you. ”
And now the banker,pacing from comer to comer,recalled all this and asked himself,“Why did I make this betWhat’s the goodThe lawyer lost fifteen years of his life and I threw away two millions. Will it convince people that capital punishment is worse or better than imprisonment for lifeNo,no!Rubbish!On my part,it was the caprice(心血来潮)of a well-fed millionaire;on the lawyer’s part,it’s the pure greed of gold. ”
The lawyer would choose life imprisonment because______.

A.he was younger than the banker
B.capital punishment was immoral
C.it was better than capital punishment
D.the banker would give him $200,000

4.单项选择题The book fair has received a positive______from readers.

A.result
B.response
C.settlement
D.solution

5.单项选择题If the operation______carefully prepared,it would not have been successful.

A.was not
B.has not been
C.had not been
D.were not

6.单项选择题Having decided to rent a flat,we______contacting housing agencies in the city.

A.set about
B.set down
C.set out
D.set up

7.单项选择题Jenny complained that the hospital______her too much for the treatment.

A.expended
B.paid
C.cost
D.charged

8.单项选择题Because of the bad weather,the sports meet had to be______.

A.shut down
B.done away
C.taken off
D.called off

10.单项选择题The central theatre has a seating______of more than 3,000 people.

A.capability
B.capacity
C.ability
D.facility