题目内容
听力原文： Scientists say sharks have lived in the world's oceans for millions of years. Scientists say there are more than three- hundred-fifty different kinds of sharks.
(14[B]) Sharks do not have bones, and a shark has an extremely good sense of smell. It can find small amounts of substances in the water, such as blood, body liquids and chemicals produced by animals. Sharks also sense electrical and magnetic power linked to nerves and muscles of living animals. These powerful senses help them find their food. Some sharks will eat just about anything. Many unusual things have been found in the stomachs of some large sharks. They include shoes, dogs, a cow's foot and metal protective clothing.
About forty percent of the different kinds of sharks lay eggs. The others give birth to live young. (15[C]) Some sharks carry their young inside their bodies like humans do.
Scientists are beginning to understand the importance of sharks to humans. (16[B]) Medical researchers want to learn more about the shark's body defense system against disease. They know that sharks recover quickly from injuries. Sharks appear never to suffer infections, cancer or heart diseases.
What is this passage mainly about？
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听力原文： Joe grew up in an orphanage. He envied rich people and decided when he grew up he could make much money.
Joe was not clever and he failed all his school exams. (17[A]) "I will either have to find a good job or I will have to become a thief." Joe said to himself. He knew he would never find an well paid job.
For months Joe watched a bank out of town. He noticed when it had the fewest customers. He watched, waited and planned.
One afternoon he found that only two tellers were on duty. "I will either succeed and be very rich or fail and go to prison." said Joe. He was willing to take the risk.
Then he walked in and pushed a demand note over the counter, (18[B]) The teller read it, turned pale and quietly opened a small safe behind him. He took out $50,000 and placed the bank notes in Joe's open bag. Then Joe ran as fast as he could.
That night Joe had to bury money incase the police caught him. He chose a deserted piece of land near the house, he was glad when the money was safely hidden in the ground.
The next day he was woken by bangs on his door. He answered and there came two policemen. "Joseph Smith, you are under arrest for robbing a bank!"
Joe protested in vain. (19[A]) The bank had hidden cameras and the whole raid had been photographed. Joe was caught and put into prison.
Ten years later Joe was set free. He quickly made his way to the spot where he had buried the money.
A big building had been built on the site.
By what means did Joe think he could become rich？
(28[A]) The United States President had dismissed this weekend's Bosnian Serb referendum as a maneuver to buy time. He is expected to press reluctant Europeans for military action against Bosnia's Serbs if they do reject the apparently doomed Vance Owen plan.
Tangled fighting between the three races broke out ______.
SECTION B PASSAGES
Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow.
听力原文： We all scream for water when thirsty. (15[A]) But do you know in very hot, dry weather plants also make faint sounds— as if they're crying out for help？
You see, in a plant's stem there're hundreds of "water pipes" that bring water and minerals from the soil all the way up to the leaves. As the ground turns dry, it becomes harder and harder for the plants to do this.
In severe droughts, plants have to fight to pull out any water available. Scientist Robert Winter has found out that when it is really bad their water pipes snap from the tension like rubber bands. When that happens, the whole plant vibrates a little. The snapping pipes make noises 10,000 times quieter than a whisper.
Robert knows that healthy, well-watered plants are quiet. (16[D]) He also knows that many insects prefer attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not？ Robert thinks that the insects may listen for the plants that cry. And then they may buzz in to kill.
To test his theory, Robert is using a device that can imitate plant cries. He attaches it to a quiet, healthy plant so the plant sounds thirsty. Then he watches insects lo see if they attack more often than usual.
If he is right, scientists could use the insects' ability against them. (17[D]) They could build traps that imitate crying plants. So when the insects buzz in to eat, they won't buzz out.
What do plants do when they are thirsty？
听力原文： (24[A]) Northern Ireland peace talks resumed yesterday with negotiations under orders from the US Chairman George Mitchell, former US Senator, (23[C]) to stop haggling and get down to the business of solving the worst violence in the province,
"The time has come to get down to serious negotiations and not to waste your time on full stops and commas. There is an urgent need for this process to proceed." George Mitchell said.
The talks, launched with fanfare by the British and Irish governments in June 12, started, however, without representatives of the key players, the IRA guerrillas fighting the British rules.
Who is George Mitchell？
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