40. Why didn't Slater get the kind of reward he expected? A)Because the headmaster had forget it, probably B) Because the lecturer did not agree to give him any reward C) Because the headmaster never meant to give the usual kind of reward to anyone D) Because the he er did not keep his word Why don't birds get lost on their long migratory flights from one place to another? Scientists have puzzled over this question foe many years. Now they are beginning to fill the blanks. Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that mainly fly by night? Tests with artificial stars have proved that night-flying birds are able to follow the stars in their long-distance flights One such birds-a warbler(a]14)-had spent its lifetime in a cage and had never flown under a natural sky at migration time. 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 make-belief stars caused a change in the direction of hi flight Scientists thought that warblers, when flying in the daylight, use the sun for guidance. 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, cost lines, and river course. But when it's too dark to see these, the warblers circle helpless, unable to get their bearings(j a/ k). (69%) I.The reason why birds don't get lost on their long migratory flights A)has been known to scientists for years B) has only recently been discovered C)is known by everyone D)will probably remain a mystery 2. During daylight hours, birds B)rely on landmarks C)use the sun for guidance D)are more likely to get lost 3. By "his out cousins" the author means A)other experimenters B)the other warblers of the same brood C)warblers under the natural sky D)other birds in general 4. The experiment with the warbler indicated that birds have to be taught to navigate a bird that has been caged cannot fly long distance some birds cannot fly at night G)some birds seem to follow the stars when they fly at night 5. In total darkness. warblers A)use landmarks B)don't know which way to fly C) fly back home D) wait for the stars to appear40. Why didn’t Slater get the kind of reward he expected? A) Because the headmaster had forget it, probably. B) Because the lecturer did not agree to give him any reward. C) Because the headmaster never meant to give the usual kind of reward to anyone. D) Because the headmaster did not keep his word. 5 Why don’t birds get lost on their long migratory flights from one place to another? Scientists have puzzled over this question foe many years. Now they are beginning to fill the blanks. Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that mainly fly by night? Tests with artificial stars have proved that night-flying birds are able to follow the stars in their long-distance flights. One such birds – a warbler (刺嘴莺) – had spent its lifetime in a cage and had never flown under a natural sky at migration time. 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 make-belief stars caused a change in the direction of his flight. Scientists thought that warblers, when flying in the daylight, use the sun for guidance. 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, cost lines, and river course. But when it’s too dark to see these, the warblers circle helpless, unable to get their bearings(方向感). (69%) 1.The reason why birds don’t get lost on their long migratory flights _________. A) has been known to scientists for years B) has only recently been discovered C) is known by everyone D) will probably remain a mystery 2. During daylight hours, birds ________. A) fly aimlessly B) rely on landmarks C) use the sun for guidance D) are more likely to get lost 3. By “his out cousins” the author means _______. A) other experimenters B) the other warblers of the same brood C) warblers under the natural sky D) other birds in general 4. The experiment with the warbler indicated that __________. birds have to be taught to navigate a bird that has been caged cannot fly long distance some birds cannot fly at night G) some birds seem to follow the stars when they fly at night 5. In total darkness, warblers ________. A) use landmarks B) don’t know which way to fly C) fly back home D) wait for the stars to appear