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Why don’t birds get lost on their long flights from one place to another Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks. Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly at night Tests with artificial stars have proved that certain night—flying birds are able to follow the stars in their long-distance flights. A dove had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the position of the artificial stars caused a change in the direction of his flight. But the stars are apparently their principal means of navigation. When the stars are hidden by clouds, they apparently find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the doves circle helplessly, unable to find their way. In total darkness, doves ______.
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His ignorance of the company’s financial situation results in his failure to take effective measures.
I was telling my boy Tony the story of the hare (野兔) and tortoise (乌龟). In the end I said, "Son, remember: slow and steady, but wins the race. Don’t you think there’s something to learn from the tortoise" He opened his eyes wide. "Do you mean next time when I’m entering for the 60-meter race, I should wish that Billy and Tom and Sandy would all fall asleep half-way" I was shocked. "But the tortoise didn’t wish the hare would fall asleep!" "He must have wished that," Tony said. "Otherwise how could he be so stupid as to race with the hare He knew very well the hare ran a hundred times faster than he himself did." "He didn’t have such a wish," I insisted. "He won the race by perseverance (坚韧不拔), by pushing on steadily." Tony thought for a while. "That’s lie," He said. "He won because he was lucky. If the hare hadn’t happened to fall asleep, the tortoise would never have won the race. He could be as steady as you like, or a hundred times steadier, but he’d never have won the race. That’s for sure." I gave up. Today’s children are not like what we used to be. They are just hopeless. , According to the passage, who do you think learnt a lesson
A—ambulance B—credit card C—website D—catalogue E—on vacation F—metro G—download H—be clearly marked and priced I—network games J—traffic jams K—magazine cover L—house to let M—IT N—campus life O—sale discount ( )度假 ( )销售折扣
Why don’t birds get lost on their long flights from one place to another Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks. Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly at night Tests with artificial stars have proved that certain night—flying birds are able to follow the stars in their long-distance flights. A dove had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the position of the artificial stars caused a change in the direction of his flight. But the stars are apparently their principal means of navigation. When the stars are hidden by clouds, they apparently find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the doves circle helplessly, unable to find their way. The experiment with the dove indicated that ______.
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