When you think about math, you probably don’t think about breaking the law, solving mysteries or finding criminals. But a mathematician in Maryland does, and he has come up with mathematical tools to help police find criminals.

　　People who solve crimes look for patterns that might reveal (揭示) the identity of the criminal. It’s long been believed, for example, that criminals will break the law closer to where they live, simply because it’s easier to get around in their own neighborhood. If police see a pattern of robberies in a certain area, they may look for a suspect who lives near the crime scenes. So, the farther away from the area a crime takes place, the less likely it is that the same criminal did it.

　　But Mike O’Leary, a mathematician at Towson University in Maryland, says that this kind of approach may be too simple. He says that police may get better clues to the location of a criminal’s home base by combining these patterns with a city’s layout (布局) and historical crime records.

　　The records of past crimes contain geographical information and can reveal easy targets — that is, the kind of stores that might be less difficult to rob. Because these stores are along roads, the locations of past crimes contain information about where major streets and intersections are. O’Leary is writing a new computer program that will quickly provide this kind of information for a given city. His program also includes information about the people who live in the city, and information about how a criminal’s patterns change with age. It’s been shown, for example, that the younger the criminal, the closer to home the crime.

　　Other computer programmers have worked on similar software, but O’Leary’s uses more math. The mathematician plans to make his computer program available, free of charge, to police departments around the country.

　　The program is just one way to use math to fight crime. O’Leary says that criminology — the study of crime and criminals — contains a lot of good math problems. “I’m the only one who knows what gold looks like,” he says. “It’s a lot of fun.”

　　49. To find criminals, police usually _________.

　　A. check who are on the crime scene

　　B. seek help from local people

　　C. depend on new mathematical tools

　　D. focus on where crimes take place

　　50. O’Leary is writing a computer program that _________.

　　A. uses math to increase the speed of calculation

　　B. tells the identity of a criminal in a certain area

　　C. provides the crime records of a given city

　　D. shows changes in criminals’ patterns

　　51. By “I’m the only one who knows what gold looks like”, O’Leary means that he _________.

　　A. is better at finding gold than others

　　B. is the only one who uses math to make money

　　C. knows best how to use math to help solve crimes

　　D. has more knowledge of gold than other mathematicians

　　52. What is the main idea of the text?

　　A. Math could help police find criminals.

　　B. Criminals live near where crimes occur.

　　C. Crime records could be used to fight crime.

　　D. Computer software works in preventing crimes.

短文改错

That evening I was doing my lesson. It was about　　   1．________　　

9 o'clock. I heard strange noise which sounded　　   2．________　 

like the flowing of water. Suddenly I found the　　　  3．________　

 walls shaking as if someone was pushing it. Thinking  4．________

perhaps I was such tired, I stood up, and was going    5．________

to bed. Just then I heard someone to shout “Earth－   6．________　

quake!” The word put much fear into everyone heart.　 7．________　

 I rushed out of the house as quick as possible. The 　8．________

whole street was already filled up people. I felt　　  9．________　　

everything was trembling. The earthquake last a few    10．________

 seconds. Then everything was quiet again.

　

　　

　

完形填空：

　　Three men came to Dover Station at about nine o'clock one evening. They asked the assistant what time the next train was for London. The assistant said, “You've just 1 one. They go every hour. The next one is at ten o'clock. ”“That is 2 ,”they said, “we'll go and have a drink.”So they went to the nearest bar. A minute or two after ten o'clock, they came 3 and said to the assistant, “Has the train gone?” “Yes,” he said, “it went at ten o'clock 4 I told you. The next is at eleven o'clock.”

　　“That's OK,” they said, “we'll go and have another 5 .”So they went back to the bar.

　　They missed the eleven o'clock train in 6 way, and the assistant said, “Now, the next train is the 7 one; If you miss that, you 8 to London tonight.”

　　Twelve o'clock came, and the last train 9 out, when 10 of them came out of the bar running as hard as they 11 . Two of them got into a carriage just 12 the train was leaving but the third one didn't run 13 , and the train went out leaving him 14 . He stood there looking at the train and 15 , as if 16 a train was the best joke (玩笑) in the world. The assistant went up to him and said, “I told you that this was the last train. Why didn't you come 17 ?”

　　The man couldn't answer because of laughing. He laughed 18 the tears came into his eyes. Then he said, “Did you see those two fellows 19 into the train and leave me here?”

　　“Yes, I saw them,” said the assistant.

　　“Well, I was the one who was going to London; they only came 20 to see me off!”

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　　When I came out of my office, it was dark. In order to get home as soon as possible, I hired a taxi. The car was __(1)___ along the road, now well-lit, now sank in darkness. I broke the __(2)___ on purpose, __(3)___ that the driver might be too tired to drive,“When do you go back home in the evening?”

　　“Nine o'clock. I'll go after this trip.”

　　“Then when do you come out in the morning?”I __(4)___ another question.“Nine o'clock, too. And I go home for lunch and dinner, just as if I worked at an office.”His easiness surprised me, because every time I ride in a taxi, what I hear from the __(5)___ is only complaint（抱怨）. They complain that they __(6)___ work __(7)___, that it is __(8)___ to earn money, that they are bullied（欺侮）by the policemen, or that the corporation leaders are seated __(9)___ and enjoy the __(10)___ of others' work. It seems that they have a grievance（不满意）against everything. But this driver told me,“I find it __(11)___ to be a section chief as I was before. I don't like management work. I like driving, just for __(12)___. It's __(13)___ that I __(14)___ drive without a passenger. So I can earn two to three thousand yuan a month with ease. Any __(15)___? Yes, I never follow an empty taxi. If it goes __(16)___, I go northward. If it goes along the highway, I turn into a __(17)___ street. In this way I always get customers.”

　　His words showed his satisfaction with his life and the pride he __(18)___ in his job. Such feelings are __(19)___ among people nowadays as oxygen in high mountains. As an ancient saying __(20)___,“Neither joy in material gains nor grieve over personal setbacks（挫折）.”How many people nowadays can show high ideals by simple living and go far with a calm mind? I couldn't help feeling curious when I found such a state of mind in a stranger on a cold winter night.

(1)A．driving		B．flying	C．running	D．rushing
(2)A．calmness			B．quietness
C．stillness			D．silence
(3)A．for fear			B．on condition
C．in order			D．in case
(4)A．gave out			B．threw out
C．let off			D．set off
(5)A．taxis			B．radios
C．passengers			D．drivers
(6)A．have to			B．must
C．need			D．should
(7)A．from night till morning			B．from morning till night
C．from morning till afternoon			D．from morning till dusk
(8)A．hard			B．easy
C．possible			D．impossible
(9)A．busy	B．busily		C．lazy	D．lazily
(10)A．results			B．achievements
C．gains			D．fruits
(11)A．tired			B．tiring
C．excited			D．exciting
(12)A．pleasure			B．money
C．work			D．interest
(13)A．unfortunate			B．fortunate
C．likely			D．wise
(14)A．often	B．usually		C．hardly	D．seldom
(15)A．trick	B．secret		C．skill	D．method
(16)A．southward			B．northward
C．eastward			D．westward
(17)A．wide	B．narrow		C．lonely	D．empty
(18)A．had	B．made		C．kept	D．took
(19)A．common	B．rare		C．much	D．little
(20)A．says	B．suggests		C．goes	D．talks