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If the eyes are the romantic’s window into the soul, then the teeth are an anthropologist’s ( 人類學(xué)家 ) door to the stomach.

   In a study published last month in the journal Science, Peter Ungar of the University of Arkansas and his partner, Matt Sponheimer of the University of Colorado, US, examined the teeth of our early human ancestors to find out what they were really eating.

   They already knew that different foods cause different marks on teeth. Some cause scratches, while others cause pits (坑).The carbon left on teeth by different foods is also different. Tropical grasses, for example, leave one kind of carbon, but trees leave another kind because they photosynthesized ( 光合作用 ) differently.

   Traditionally, scientists had looked at the size and shape of teeth and skulls ( 頭骨 ) to figure out what early humans ate. Big flat teeth were taken to be signs that they ate nuts and seeds, while hard and sharp teeth seemed good for cutting meat and leaves. But this was proven wrong.

   The best example was the Paranthropus (傍人), one of our close cousins, some of which lived in eastern Africa. Scientists used to believe Paranthropus ate nuts and seeds because they had big crests(突起)on their skulls, suggesting they had large chewing muscles and big teeth. If this had been true, their teeth should have been covered with pits like the surface of the moon. They would also have had a particular type of carbon on their teeth that typically comes from tree products, such as nuts and seeds.

   However, when the two scientists studied the Paranthroupus, it turned out to have none of these characteristics. The teeth had a different kind of carbon, and were covered with scratches, not pits. This suggests they probably ate grass, not nuts and fruit stones. It was the exact opposite of what people had expected to find.

   Carbon “foodprints” give us a completely new and different insight into what different species ate and the different environments they lived in. If a certain species had the kind of carbon on its teeth that came from grasses, it probably lived in a tropical grassland, for example.

1.The underlined sentence in Paragraph 1 probably means that _____.

A. anthropologists can study the structure of human stomachs by studying their teeth.

B. anthropologists can study the diet of early humans by studying their teeth

C. anthropologists can learn whether humans were healthy by looking at their teeth

D. anthropologists can get the most useful information about humans from their teeth

2.According to Paragraph 3 to 5, which of the following statements is TRUE?

A. Scratches on teeth are caused by eating nuts or seeds.

B. Pits on teeth are caused by eating grass or leaves.

C. Early humans with hard and sharp teeth ate meat and leaves.

D. Different foods leave different marks and carbon on teeth.

3.The example of the Paranthropus was mentioned in the article in order to _____.

A. tell readers that they are one of our close cousins living in eastern Africa

B. tell readers they had different eating habits from modern humans

C. prove that size and shape of skulls does not show accurately what early humans ate

D. tell readers that living environment makes a difference to skull structure

根據(jù)短文內(nèi)容，從短文后的選項(xiàng)中選出能填入空白處的最佳選項(xiàng)。選項(xiàng)中有兩項(xiàng)為多余選項(xiàng)

The sea has always interested man. From it they can get food, minerals, and treasure. __1.__ But he could not go far beneath its surface __2.__. However, he is not a fish. He must breathe air, so he can’t stay under the water’s surface for any length of time. To explore deep water, man faces even more dangers and problems. A diver who wants to stay under water for more than a few minutes must breathe air or a special mixture of gases __3.__. He can carry a tank of air on his back and breathe through a nose and mouth piece. Water weighs 800 times as much as air. Tons of water pushes against a diver deep in the sea _4.__. When a diver is under great pressure, his blood takes in some of the gases he breathes. As he rises to surface, the water pressure less. If the diver rises too quickly, the gases in his blood form bubbles (氣泡). The diver is then suffering  from the bends (潛水夫病).The bends can cause a diver to double up in pain __5.__ . 

A. His body is under great pressure.

B. Scientists are trying to find more about the sea.

C. For thousands of years, he could sail on it.

D. They can even kill him.

E. He can wear a diving suit and have air pumped to him from above. 

F. The water pressure can cause a diver to breathe with difficulty. 

G. Man wants to explore deep into the sea.

下面文中共有10處語言錯誤，錯誤涉及一個單詞的增加，刪除或修改。

增加：在缺詞處加一個漏字符號（ ∧ ），并在其下面寫出該加的詞。

刪除：把多余的詞用斜線（\）劃掉。

修改：在錯的詞下劃一橫線，并在該詞下面寫出修改后的詞。

注意： 1.每處錯誤及其修改均僅限一詞；

2．只允許修改10處，多者（從第11處起）不記分。

Our government is trying hard to build an energy-saving society. It is somebody’s duty to work hard and reach this goal. Besides, not everybody has realized the important of it. Take our school for example. Sometime we can see that lights and computers are still on after class. Some students even forget to turn on the tap after using it and have water run all the time. Our papers are printed on only one side, which causing much waste. It’s time we did something to avoid this kind of waste. Firstly, make sure that all the light and other electric facilities turned off when we leave the rooms. Try to form the habit of turning off the tap immediate after using it. What’s more, papers should be printed on both sides and reused if possible.

假如你是李華,最近，你班同學(xué)就中學(xué)生是否可以帶手機(jī)上學(xué)進(jìn)行了討論。 請你根據(jù)下列信息，給校長寫一封信，客觀地介紹你班討論的情況。

1.詞數(shù):100字左右    2.經(jīng)濟(jì)負(fù)擔(dān)economic burdens.   3.信的開頭已經(jīng)為你寫好

Dear principle,

  I’m writing to tell you about the discussion we’ve had about whether a mobile phone should be brought to school. ——————————————————————————————

More and more foreign students come to China to learn________ Chinese language.

A. a                                        B. the                                    C. an                             D. 不填

 Rather than      at home alone, Little Tom      go to the cinema that day.

A. stay; preferred                                                        B. to stay; prefers to

C. stay; preferred to                                                D. stay; prefers to

Time waits for no man. But teenagers won’t realize the value of time until it’s gone.  Don’t waste your time, __________ you will regret it.

A. so                                      B. and                                    C. but                                    D. or

—Would you like something to drink, girls? 

—Yes, _______, please. 

A. two cup of coffee                              B. two cup of coffees 

C. two cups of coffee                             D. two cups of coffees

 I’m sorry I can’t join you.  I __________ my homework. 

A. haven’t finished                                                B. didn’t finish       

C. won’t finish                                                     D.  don’t finish 

 Mr. Read is the person to ___________ you should write.

A. whom   B. who               C. which       D. that