摘要: A. out B. by C. across D. from

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A "lost tribe" that reached America from Australia may have been the first Native Americans, according to a new theory.

If proved by DNA evidence, the theory will break long established beliefs about the southerly migration of people who entered America across the Bering Strait, found it empty and occupied it.

On this theory rests the belief of Native Americans to have been the first true Americans. They would be classified to the ranks of escapee, beaten to the New World by Aboriginals (土著人) in boats.

To a European, this may seem like an academic argument, but to Americans it is a philosophical question about identity (身份), Silvia Gonzales, of Liverpool University said .

Her claims are based on skeletons found in the California Peninsula of Mexico that have skulls (头骨) quite unlike the broad Mongolian features of Native Americans. These narrow-skulled people have more in common with southern Asians, Aboriginal Australians and people of the South Pacific Region.

The bones, stored at the National Museum of Anthropology (人类学) in Mexico City, have been carbon-dated and one is 12,700 years old, which places it several thousand years before the arrival of people from the North. "We think there were several migration waves into the Americas at different times by different human groups," Dr. Gonzales said. "The timing, route and point of origin of the first colonization of the Americas remains a most contentious topic in human evolution."

But comparisons based on skull shape are not considered conclusive by anthropologists, so a team of Mexican and British scientists, backed by the Natural Environment Research Council, has also attempted to take out DNA from the bones. Dr. Gonzales declined yesterday to say exactly what the results were, as they need to be checked, but indicated that they were consistent(一致) with an Australian origin.

It is generally considered that the first Native Americans came from _____.

       A.North Asia      B.Australia   C.South Pacific   D.South Asia

The skeletons found in the California Peninsula of Mexico have _____.

       A.the broad skull shape     

       B.the narrow skull shape

       C.different features of Aboriginal Australians   

       D.the same features of Native Americans

The underlined “contentious” is similar in meaning to “_____”.

       A.likely to cause great interest    B.difficult to solve

       C.well-known to all           D. likely to cause argument

Which of the following statements is true according to the text?

       A.Research on skulls can draw an exact conclusion.

       B.DNA tests have proved the fact that the first Native Americans came from Australian.

       C.Scientists are still not sure about the origin of the Native Americans.

       D.People began to enter America across the Bering Strait about 12,700 years ago.

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A new study says one part of the human brain may become smaller as the result of a condition known as jet lag. Jet lag results from flying long distances in an airplane. People with jet lag may feel extremely tired for several days. They may also have problems thinking clearly and remembering.

Recently a researcher at the University of Bristol in Britain reported the findings of his jet lag study, which involved twenty young women who worked for international airlines. They had served passengers on airplanes for five years. These flight attendants flew across many countries and at least seven time zones. In the study, the flight attendants had different amounts of time to recover from jet lag. Half the women spent five days or fewer in their home areas between long flights The other half spent more than fourteen days in their home areas.

The researcher took some saliva from the women's mouths to measure levels of a hormone(荷尔蒙) that increases during stress (紧张). He tested them to see if they could remember where black spots appeared on a computer screen. And he took pictures of their brains to measure the size of the brain's temporal lobes (脑叶).

It was found that the women who had less time between flights had smaller right temporal lobes. This area of the brain deals with recognizing and remembering what is seen. The same group performed worse and had slower reaction times on the visual memory test. And their saliva samples showed higher levels of stress hormones.

The researcher believes the brain needs at least ten days to recover after a long trip. He says airline workers told him their ability to remember got worse after working on planes for about four years. Other studies have shown that increased feelings of stress can cause a loss of cells in the part of the brain that controls memory.

Scientists say more tests are needed to study the effects of jet lag on the brain. They want to find out if too much jet lag could permanently (永久性的) affect memory.

According to the text, jet lag _________.

A. can cause difficulties in speaking

B. can make people feel tired for a few weeks

C. can be only found in flight attendants

D. can be caused by flying over several time zones

It can be inferred from the text that _________.

A. the conclusion is refused by many scientists

B. scientists fear that this research is not done properly

C. every scientific conclusion needs the support from many tests

D. the women who were examined in the research were not healthy

From the result of the research we can see that _________.

A. the women who have longer rest at home show better memory

B. the women who fly in short time have smaller right temporal lobes

C. the women who have longer flights fail the memory test

D. the women who rest more than 14 days produce less hormones

What is the subject discussed in the text?

A. The cause of jet lag.      B. A story of a group of flight attendants.

C. The importance of having enough rest after flights.

D. A research about the effects of jet lag on the brain.

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A few weeks after my first wife, Georgia, was called to heaven, I was cooking dinner for my son and myself. For a   16 , I had decided on frozen peas. As I was cutting open the bag, it   17  from my hand and crashed to the floor. The peas, like marbles,   18  everywhere. I tried to use a broom,   19  with each swipe they just rolled across the kitchen.
For the next week, every time I was in the   20 , I found a pea---in a corner, or behind a table leg. They kept   21 . Eight months later I pulled out the refrigerator to clean behind it, and   22  12 frozen peas hidden underneath.
At the time I found those few remaining   23 , I was in a new relationship with a wonderful   24  I’d met in a support group. After we married, I was reminded 25  those peas under the refrigerator, and realized that my   26  had been like that bag of frozen peas. It had shattered(破碎. My wife had died; I was in a new city with a busy job, and with a son having trouble   27  his new surroundings and the  28  of his mother. I was a bag of spilled frozen peas; my life had come apart and scattered.
When life gets you   29 , when everything you know comes apart, and when you think you’ll never  30 , remember that it’s just a bag of scattered frozen peas. The peas can be  31 , and life will move on. You’ll find all the peas   32 , including the ones that are hardest to find. And when you’ve got them   33  you’ll start to feel whole again.
The life you know can break apart at any time. But you’ll have to   34 , and how fast you collect your peas depends on you. Will you keep scattering them around with a broom,  35  will you pick them up one by one and put your life back together?

【小题1】
A.drinkB.fruitC.vegetableD.meat
【小题2】
A.movedB.walkedC.ranD.slipped
【小题3】
A.rubbed B.rolledC.grew D.existed
【小题4】
A.but B.andC.although D.so
【小题5】
A.bedroom B.living roomC.kitchenD.storeroom
【小题6】
A.getting up B.turning upC.taking upD.using up
【小题7】
A.foundB.ateC.left D.planted
【小题8】
A.presentsB.cans C.vegetablesD.peas
【小题9】
A.man B.childC.womanD.boy
【小题10】
A.ofB.forC.with D.in
【小题11】
A.wifeB.life C.sonD.friend
【小题12】
A.turning toB.leading toC.adjusting to D.adding to
【小题13】
A.thank B.love C.help D.loss
【小题14】
A.downB.near C.closeD.wide
【小题15】
A.get itB.make itC.take itD.leave it
【小题16】
A.grewB.boughtC.collectedD.frozen
【小题17】
A.eventuallyB.fortunatelyC.properly D.specially
【小题18】
A.bothB.allC.eitherD.each
【小题19】
A.call onB.put onC.bring on D.move on
【小题20】
A.while B.becauseC.sinceD.or

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D
The recent, apparently successful, prediction by mathematical models of an appearance of El Nino—the warm ocean How that periodically develops along the Pacific coast of South America has excited researchers.Jacob Bjerknes pointed out years ago how winds might create either abnormally warm or abnormally cold water in the eastern equatorial (赤道附近的) Pacific.Nevertheless, before the creation of the models, no one could explain why conditions should regularly change between appearances of the warm El Nino and the so-called anti-El Nino.The answer, at least if the current model that links the behavior of the ocean to that of the atmosphere is correct, is to be found in the ocean.
It has long been known that during an El Nino, two conditions exist: unusually warm water extends along the eastern Pacific and winds blow from the west into the warmer air rising over the warm water in the east.The contribution of the model is to show that the winds of an El Nino, which raise sea level in the east, send a signal to the west lowering sea level at the same time.According to the model, that signal is created as a negative (负的) Rossby wave, a wave of lower sea level, that moves westward parallel to the equator at 25 to 85 kilometers per day.Taking months to move across the Pacific, Rossby waves march to the western boundary of the Pacific basin, which is modeled as a smootli wall but in reality consists of quite irregular island chains.
When the waves meet the western boundary, they are reflected, and the model predicts that Rossby waves will be broken into many coastal Kelvin waves carrying the same negative sea-level signal.These eventually shoot toward the equator, and then head eastward along the equator drove by the earth at a.speed of about.250 kilometers per day.When enough Kelvin waves of adequate amplitude (振幅) arrive from the western Pacific, their negative sea-level signal overcomes the feedback mechanism, raising the sea level, and they begin to drive the system into the opposite cold mode.This produces a gradual change in winds, one that will eventually send positive sea-level Rossby waves westward, waves that will eventually return as cold cycle—ending positive Kelvin waves beginning another warming cycle.
67.What is the passage mainly about?
A.How Rossby waves are found.
B.Where El Nino is formed.
C.What the models predict.
D.How the models work.
68.Where does El Nino often appear?
A.Along the western coast of the USA .
B.In the Pacific in the south, of the equator.
C.In the Pacific in the north of the equator.
D.Along the southern coast of South America.
69.What is right according to the passage?
A.Rossby waves and Kelvin waves move in opposite directions along the equator.
B.People could explain El Nino before the creation of the mathematical models.
C.Adequate sea-level waves can produce westward positive cold cycle.
D.The speed of Rossby waves is faster than that of Kelvin waves.
70.What does the underlined word "waves" in Paragraph 3 refer to?
A.Kelvin waves.       B.Sea-level signals.   C.Coastal waves.   D.Rossby waves.

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C
Reading about history is nice, but finding ties to long-ago historical events in your own backyard is really exciting.
In their heavily populated area, neighbors Adam Giles,13, and Derek Hann.12, uncovered pieces of glass that looked quite different from what’s used today. “After digging about two feet down, I came across an interesting bottle,” Derek said. The bottle had a “pontil scar” on the bottle, an indication that it was hand-blown rather than machine made. It also had the name “Fraser” on one side.
Adam found remains of a green bottle and some very thick brown glass—again, far different from today’s.
After doing research on the computer, the boys contacted Aimee Wells of the county’s Cultural Resources office. She showed them a computer program that digitally puts old maps over modern satellite photographs.
Bingo! Their back yards were once part of a military(军事的) encampment(营地) called Camp Alger used by Ohio soldiers on their way to fight in the Spanish-American War in 1898.
So how do a few bottles get connected to a brief war that was more than a century ago? “We get there by good judgment,” Wells said. “We know the time period of the bottles and what happened in that area.” Anyone can dig a hole, but archaeologists seek a deeper understanding. How do objects found relate to things around them?
When Derek and Adam realized that a solider might have held that Fraser bottle 110 years ago, they wondered what he might have been thinking. What did he see as he looked around him? How did he pass the time waiting to go into battle?
Historical records show that while waiting for orders, the soldiers in and around Camp Alger played baseball, played instruments and walked seven miles to the Potomac River once a week for baths. A spread of strange fever forced the closing of the camp, and there are no buildings to study. “What’s left is only what’s in the ground,” said Wells.
Derek’s and Adam’s back yards have joined the 3,400 places listed on the county’s register of archaeological sites. The boys were given tips on how to dig effectively and safely, and on how to document the location of items found.
The official record of their finds serves as another piece of the puzzle for historians seeking to form a more complete story of what happened.
“Not everyone is going to have historical objects in their own yard,” Wells said. “That’s okay. Make your own time capsule and bury it. What would you want people to know about your life years from now?”
63. What is the passage mainly about?
A. How Adam Giles and Derek Hann dug out the remains of an ancient military encampment.
B. What Adam Giles and Derek Hann found in their back yard and its relationship with an encampment.
C. The great contribution Adam Giles and Derek Hann made to the cause of archaeology.
D. The tips on how to dig out ancient objects buried under the ground safely and effectively.
64. From the passage, we can see that the boy’s discovery _______.
A. includes all kinds of hand-made and machine- made glass.
B. has helped historians find out what happened in 1898.
C. couldn’t have been meaningful without Aimee Wells’ help.
D. has added the county to the list of archaeologist sites.
65. When Wells said “We get there by good judgment.” (Paragraph 6), she meant that_______.
A. they have established the ties to Camp Alger by finding out the time period of the bottles.
B. they have figured out how to get to the place where the brief war happened.
C. they have managed to dig out the bottles in the back yard safely with common sense.
D. they were able to locate the soldiers who used the Fraser bottles 110 years ago.
66. Which of the following fits the description of historical records?
A. The soldiers in and around Camp Alger delighted in playing basketball in their spare time.
B. When Camp Alger was forced to close, all the buildings there were destroyed.
C. The soldiers in and around Camp Alger often buried some bottles underground as time capsules.
D. Camp Alger was forced to close because of a spread of a strange fever.

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