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1 , The sea serves the need of man because ...............
A. it provides man with sea food
B .it offers oil to man
C. it supplies man with mineral
D.all of the above
2, we can conclude from the passage that
A. The sea resources have largely been used up
B .the sea , in a broad seense , hasn't yet been developed
C. By the year 2050 ,the technology will be good enough to exploit all the sea resources
D.The problems that prevent us from fully exploting the sea have already been solved
chưa bổ bôi đen hết -.- bực quá
1 , The sea serves the need of man because ...............
A. it provides man with sea food
B .it offers oil to man
C. it supplies man with mineral
D.all of the above
2, we can conclude from the passage that
A. The sea resources have largely been used up
B .the sea , in a broad seense , hasn't yet been developed
C. By the year 2050 ,the technology will be good enough to exploit all the sea resources
D.The problems that prevent us from fully exploting the sea have already been solved
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Đáp án: B
Thông tin: More and more farmers leave the land because they can not earn enough money to survive.
Dịch: Ngày càng có nhiều nông dân rời bỏ đất vì họ không thể kiếm đủ tiền để tồn tại.
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Our oceans are becoming extremely polluted. Most of this pollution comes from the land, which means it comes from people. Firstly, there is raw sewage, which is pumped directly into the sea. Many countries, both developed and developing, are guilty of doing this. Secondly, ships drop about 6 million tons of garbage into the sea each year. Thirdly, there are oil spills from ships. A ship has an accident and oil leaks from the vessel. This not only pollutes the water, but it also kills marine life. Next, there are waste materials from factories. Without proper regulations, factory owners let the waste run directly into the rivers, which then leads to the sea. And finally, oil is washed from land. This can be the result of carelessness or a deliberate dumping of waste.
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One day in 1963, a dolphin named Elvar and a famous astronomer, Carl Sagan, were playing a little game. The astronomer was visiting an institute which was looking into the way dolphins communicate with each other. He was standing at the edge of one of tanks where several of these highly intelligent, friendly creatures were kept. Elvar had just swum up alongside him and had turned on his back. He wanted Sagan to scratch his stomach again, as the astronomer had done twice before. But this time Elvar was too deep in the water for Sagan to reach him. Elvar looked up at Sagan, waiting. Then, after a minute or so, the dolphin leapt up through the water into the air and made a sound just like the words "More!"
The astonished astronomer went to the director of the institute and told him about the incident.
"Oh, yes. That´s one of the words he knows," the director said, showing no surprise at all.
Dolphins have bigger brains in proportion to their body size than humans have, and it has been known for a long time that they can make a number of sounds. What is more, these sounds seem to have different functions, such as warning each other of danger. Sound travels much faster and further in water than it does in air. That is why the parts of the brain that deal with sound are much better developed in dolphins than in humans. But can it be said that dolphins have a "language", in the real sense of the word? Scientist don´t agree on this.
1/ The dolphin leapt into the air because
A. Sagan was too near the water
B. it was part of the game they were playing.
C. he wanted Sagan to scratch him again
D. Sagan wanted to communicate with him
2/ "Dolphins" brains are particularly well developed to
A. help them to travle fast in water
B. arrange sounds in different structures
C. respond to different kinds of sound
D. communicate with humans through sound
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Giup voi a
Read the text on the tight about the invention of semaphore. Five sentences have been removed. Choose from sentences A-F the one which fits each gap (l-4).There is one extra sentence which you do not need. There is an example at the beginning (0).
A Using ropes, these could be moved to form 49 different shapes that could be recognized easily.
B The main problem was that it could not be used during the night or on foggy days.
C These messages could be sent very quickly.
D The new republic faced enemies on all sides in the form of the forces of Britain, Austria, Holland, Prussia and Spain.
E In August 1794, it carried its first message, the news of Napoleon's victory at Le Quenoy.
F A system was built between London and the south coast, and other countries followed.
War has been called 'the mother of invention', and this was certainly true in the French Revolutionary wars in 1792. 1 | D | What the Revolutionary Government urgently needed was a reliable system of communication.
Claude Chappe, who was a priest and an engineer, had developed a telegraph system, but had not been able to test it fully. However, his brother Ignace was a member of the government, and arranged for Claude's system to be tested. It turned out to be a great success and started a new form of high-speed communication.
The two brothers had a series of towers built 5 to 10 km apart. At the top of each tower was a tall wooden mast, and they attached one horizontal and two vertical wooden beams to this mast. Claude called this system 'semaphore', which comes from the Greek meaning 'bearing a sign'. 2 (A )
Operators in each tower watched neighbouring towers through a telescope and then passed the message on to the next one in the line. The first line stretched from Paris to Lille, a distance of 2.40 km. 3 ( C). At an average speed of three signals a minute, it was carried in 20 minutes, more than 90 times faster than messengers on horseback.
Once the value of Chappe's system was understood, it soon became the standard method of communication in Europe. 4 (F ). By the time the electric telegraph was developed, France had more than 550 semaphore towers stretching 4,800km.
Unfortunately, Chappe's system had some disadvantages. 5 ( B) The towers were also expensive to maintain and the cost of staff was high. In the end, Chappe was depressed by these criticisms of his inventions and by claims from other engineers that they had invented semaphore, and he committed suicide in 1805.