Birds that are half-asleep—with one brain hemisphere（半球）alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks．

    Earlier studies have documented half-brain sleep in a wide range of birds．The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves．The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert．Birds also can sleep with both hemispheres resting at once．

    Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily．Sure enough, the end birds tended to watch carefully on the side away from their companions．Ducks in the inner spots showed no preference for gaze（注视）direction．

    Also, birds napping at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did．Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in internal spots, outer birds half-asleep during some 32 percent of napping time．

    “We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say．

    The results provide the best evidence for a long-standing assumption that single-hemisphere sleep evolved（发展）as creatures scanned for enemies．The preference for opening an eye on the lookout side could be widespread, he predicts．He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror．The mirror-side eye closed as if the reflection were a companion and the other eye stayed open．

    Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals．Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning．

    Studies of birds may offer unique insights（深刻的理解）into sleep．Jerome M．Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg．” He supposes that more examples may turn up when we take a closer look at other species．

1.According to the passage, birds often half sleep because ______．

       A．they have to watch out for possible attacks

       B．their brain hemispheres take turns to rest

       C．the two halves of their brain are differently structured

       D．they have to constantly keep an eye on their companions

2.What is implied about the example of a bird’s sleeping in front of a mirror?

       A．An imagined companion gives the bird a sense of security．

       B．Birds prefer to sleep in pairs for the sake of their security．

       C．The phenomenon of birds napping in pairs is widespread．

D．A single pet bird enjoys seeing its own reflection in the mirror．

3.While sleeping, some water animals tend to keep half awake in order to ______．

A．alert themselves to the approaching enemy

       B．emerge（浮现）from water now and then to breathe

       C．be sensitive to the ever-changing environment

       D．avoid being swept away by rapid currents

4.By saying “just the tip of the iceberg”, Siegel suggests that ______．

       A．half-brain sleep has something to do with icy weather

       B．the mystery of half-brain sleep is close to being solved

       C．most birds living in cold regions tend to be half sleepers

       D．half-brain sleep may exist among other species

I ran across an old photo of him the other day, thinking of some old things. He’s been dead for 25 years. His name was Rex.

36  was his favorite recreation(娱乐). He had so much 37 in the water as any person I have known. You didn’t have to throw a stick in the water to 38 him to go in. Of course, he would bring back a stick to you if you 39 throw one in.

That 40 me of that night, 41 he brought back a small box that he found somewhere--- how 42 nobody ever knew. Since it was Rex, it 43 easily have been half a race. The box wasn’t a good one. It was just a 44 old piece that somebody 45. Still it was something he wanted, probably 46 there was some difficulty in transportation（运输）. And that he thought could test his courage. We first knew about his achievement when, deep in the night, we 47 him trying to get the box up onto the porch(门厅). It sounded 48 two or three people were trying to tear the house 49 . We came downstairs and turned on the 50 light. Rex was on the top step trying to pull the thing up, but it had 51somehow. And he was just holding his own(坚持着). I suppose he would have held his own 52 dawn if we hadn’t helped him. The next day we carried the box miles away and threw it out. If we had thrown it out in a 53 place, he would have brought it home again, as a small token(象征)of his strength in such matters. 54, he had been taught to carry heavy wooden objects about and he was 55 of his skill.

Ⅱ语言知识及应用(共两节，满分35分)
第一节 完形填空(共10小题；每小题2分，满分20分)
阅读下面短文，掌握其大意，然后从21—30各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
People joke that the number of pet dogs in Beijing is more than the urban population. It is an exaggeration to some but Beijingers seem to  21      their pets more than most.
Over the past 15 years, the number of pet dogs in the city has  22  dramatically, right after the local government lifted a ban. Now Beijing is home to more than 1 million  23      according to recent statistics.
Day or night, if you walk into any residential area, it will be easy to spot someone  24     their dog. Often, there is no lead attached to the puppy, which makes it more like a  25      companion rather than an animal. They  26     stroll (漫步) at the same leisurely, carefree pace.
If they meet their neighbors with dogs too, then two  27    emerge（出现）at once: One is for people to engage in gossip, the other is for dogs to career madly around the playground. That is one of the most  28    things I have seen in the city.
But some Beijingers spoil their dogs too much.  29    during winter, when they dress their pets up as living toys with colorful vests and even pairs of homemade  30     . I pity these dogs deeply, and realize how  civilized they have become.
21. A. feed                   B. love                        C. hate                D. play
22. A. risen                   B. raised                C. reduced                   D. got
23. A. people                B. animals                    C. schools                     D. dogs
24. A. walking                     B. training                    C. playing                    D. feeding
25. A. man                   B. woman                     C. human                     D. child
26. A. never                  B. always                     C. seldom                     D. once
27. A. groups                B. classes               C. men                        D. dogs
28. A. excited               B. boring               C. important                 D. interesting
29. A. Beautifully          B. Specially                  C. Especially         D. Strangely
30. A. hats                    B. boots                       C. clothes                     D. toys

Birds that are half-asleep—with one brain hemisphere (半球) alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have documented half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze direction.
Also, birds napping at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in internal spots, outer birds half-asleep during some 32 percent of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep evolved as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
72. According to the passage, birds often half sleep because ______.
A. they have to watch out for possible attacks
B. their brain hemispheres take turns to rest
C. the two halves of their brain are differently structured
D. they have to constantly keep an eye on their companions
73. What is implied about the example of a bird’s sleeping in front of a mirror?
A. An imagined companion gives the bird a sense of security.
B. Birds prefer to sleep in pairs for the sake of their security.
C. The phenomenon of birds napping in pairs is widespread.
D. A single pet bird enjoys seeing its own reflection in the mirror.
74. While sleeping, some water animals tend to keep half awake in order to ______.
A. alert themselves to the approaching enemy
B. emerge from water now and then to breathe
C. be sensitive to the ever-changing environment
D. avoid being swept away by rapid currents
75. By saying “just the tip of the iceberg”, Siegel suggests that ______.
A. half-brain sleep has something to do with icy weather
B. the mystery of half-brain sleep is close to being solved
C. most birds living in cold regions tend to be half sleepers
D. half-brain sleep may exist among other species

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有多余选项。

The Dark Age of Greece

【小题】Among early civilizations, we call the low points "dark ages", because civilizations often dropped to such a low level that it is hard to get an accurate picture of their history during these periods. During a dark age, a civilization may not have produced monuments, statue, or other objects which we use to learn about early civilizations.

One' of the most important dark ages was the dark age of Greece,which lasted from about 1100 BC to 900 BC. Prior to-that-time,Greece had a highly advanced society called the Mycenaean civilization. The Mycenaeans were a trading civilization1.In fact, the Mycenaean civilization was so important that when it collapsed in the 12th centuryBC,most other civilizations in the region collapsed as well.The next 200 years are like a blank page to  historians and we know very little about this period.2.The collapse of the Mycenaeans brought an end to writing in the area, and thus an end to the written records historians rely on.

The little that we know about this period has been learned from archaeology. It seems that civilization became much less advanced. The pottery from this period is much simpler and less artistic. This suggests that there was lack of wealthy people to buy higher quality products. 3.   This would suggest a large decrease in population, possibly due to a widespread lack of food and consequent starvation.

Sometime around 800 BC, the Greeks began to emerge from this dark age, most probably due to the influence of other civilizations. They had lost their early writing system, but began to use the writing system of the Phoenicians at this time.4.Over the next 300 years, their civilization continued to rise, and their dark age was forgotten.

A.Many civilizations undergo a series of high points and low points during their history.

B.Many early civilizations underwent dark ages, but Greece never recovered from its dark age.

C.They began constructing larger cities and trading with their neighbors again.

D.Another interesting point is that most of the large cities of earlier time periods appear to have been abandoned in favor of much smaller settlements.

E.Many pieces of evidence suggest that there was a huge increase in population during the dark age of Greece.

F.and they did much to spread their culture across the eastern Mediterranean.

G.One major reason for this is that writing basically stopped.