题目内容

Carbon dioxide ___ from burning fuels is the most common of the so-called greenhouse gases.

A. producing                                           B. having been produced

C. to be produced                                          D. produced

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A 14-year-old girl was attacked by a grey bear while competing in a bike race. She managed to whisper the word "bear" to her rescuer. The girl suffered serious head, neck and leg wounds and is now in a dangerous condition in hospital. The girl was taking part in a 24-hour race through Bicentennial Park in Alaska when she was attacked by the bear. Bicentennial Park is next to Chugach State Park where the wild animals live. The bear attacked the girl in a heavily wooded area at about 1:30 am, during the darkest part of the night. The girl called emergency services but she was unable to communicate. Another rider Peter Basinger found her sitting dazed (神志不清的) on the ground. He told the Anchorage Daily Newsshe managed to say the word "bear" when he stopped to help. Her helmet (头盔) had been ripped off (撞掉) in the attack and rolled into the woods. Mr. Basinger waited with the girl for about 20 minutes until doctors arrived. Armed police trekked (长途跋涉) 3km with doctors to pick up the girl. Animal expert Rick Sinnott said something must be done as soon as possible to prevent the bear from attacking people again. "It had to be extremely terrifying, "he said. Mr. Sinnott told the Anchorage Daily News that the bear could have been a mother. It hurt two runners on a nearby path two weeks ago. He also said that the girl was lucky to have been wearing a bike helmet because the bear had bitten her head.

66. When did the accident happen?

A. Late in the morning.        B. Early in the afternoon.

C. In the middle of the day.     D. In the middle of the night.

67.When the girl was attacked, she was __________.

A. waiting for Peter Basinger      B. following a mother bear

C. competing in a 24-hour race     D. riding in Chugach State Park

68. Mr. Sinnott said the girl was lucky because _________.

A. she was then in a heavily wooded area  B. she was then wearing a bike helmet

C. she didn’t get hurt badly              D. she was rescued by another rider

69. What would be the best title for the passage?

 A. Girl Attacked by Bear during Bike Race    B. Watch out for Mother Bears

C. Stop Bike Races in Parks                 D. Do Remember to Wear Bike Helmet

The whole body is covered with skin.The surface of the skin is dead(like the hair and the nails),but it is made from a living layer(层)just under the surface.The outside dead layers wear off(磨损)all the time,with new ones replacing them,and the body forms a totally new skin every three weeks.

The skin protects the body from the outside world and it passes information from the outside.It helps to keep water in the body and to keep the body at the same temperature.Becteria(细菌)can’t get in through the skin unless it is damaged.

If the weather is cold,the blood vessels(血管)in the skin squeeze down,or contract(收缩),so that as little blood as possible comes near the surface.This means that less warmth is lost to the outside.This makes the skin look pale,or even “blue”.At the same time,the hairs on the skin are pulled upright by tiny muscles.

When it is hot,the blood vessels expand(扩大),or get wider again,to allow plenty of blood to run near the surface of the skin.This helps the body to lose heat,and the skin may look red.At the same time,the sweat glands(汗腺)produce more sweat,which cools the skin.

If your skin has ever been numb(麻木的),you will realize how important the feeling from the skin is.Nerves(神经)in the skin are sensitive(敏感的)to heat and cold,sharpness,hardness and softness,wetness and dryness and pain.If one is not able to feel these things,which can act as warnings,he is likely to be burned,cut or hurt in other ways.

The colour of the skin depends on special colour cells(细胞).These are just below the top layers of the skin.They are needed as protection from some harmful ray of the sun.The stronger the sun is,the more important it is to have a dark skin.People with pale skins may “tan”(晒黑)in the sun.This happens when the body produces extra colour cells in the skin for protection.In the sun,the skin produces a vitamin(vitamin D)which is needed for strong bones.

61.Which of the following statements is NOT true?

A.Our hair and nails are dead like the surface of the skin.

B.There is skin all over our body.

C.The skin of our bodies will be completely different in three weeks.

D.The surface of the skin is made of a living layer.

62.The second paragraph mainly tells us about______.

A.the functions of the skin

B.the information from the outside

C.the water in the body

D.the temperature of the body

63.Bacteria will get in through the skin______.

A.when one’s skin is numb

B.when one is ill

C.when the skin is cut

D.when the sweat glands produce more sweat

64.When the weather is cold,the skin will contract in order to______.

A.allow more blood near                                          B.make the skin look blue

C.keep warmth                                                 D.help the body lose heat

65.The colour of the skin is determined by______.

A.the rays of the strong sun                               B.colour cells

C.top layers of the skin                                           D.vitamin D

When I was at university, I studied very hard. But a lot of my friends did very little work. Some did just enough to pass exams. Others didn't do quite enough. Fred Baines was one of them. He spent more time drinking in the Students' Union than working in the library.

 Once, at the end of the term, we had to take an important test in chemistry. The test had a hundred questions. Beside each question, we had to write "True" or "False". While I was studying in my room the night before the test, Fred was watching television. Fred usually worried a lot the night before a test. But on that night he looked perfectly calm. Then he told me of his plan.

 "It's very simple. There are a hundred questions and I have to get fifty correct to pass the test. I'll take a coin into the examination room. I haven't studied a chemistry book for months, so I'll just toss(抛) the coin. That way, I'm sure I'll get half the questions right."

The next day Fred came cheerfully into the examination room. He sat tossing a coin for half an hour as he marked down his answers. Then he left, half an hour before the rest of us.

The next day, he saw the chemistry professor in the corridor (走廊).

"Oh, good," he said. "Have you got the result of the test? What mark did I get?"

    The professor looked at him and smiled.

 "Ah, it's you, Baines. Just a minute."

    Then he reached into his pocket and took out a coin. He threw it into the air, caught it in his hand and looked at it.

    "I'm terribly sorry, Baines," he said, "you failed."

61. Fred Baines          .

A. spent quite some time working in the Students' Union

B. worked hard at his lessons but he failed again and again

C. often failed his tests

D. wouldn't work hard so long as he could pass a test

62. Fred looked perfectly calm before the chemistry test because        .

 A. he was already well prepared for it

 B. he didn't think the test was so important for him

 C. someone had promised to help him out

 D. he believed he had found out a way to pass the test without any difficulty

63. The students were required to finish the test within       .

 A. half an hour   B. an hour   C. three quarters   D. an hour and a half

64. After the test, Baines was       .

 A. sure that he would pass it             

B. anxious to know the result

 C. sorry that he cheated during the test  

D. discouraged because he'd probably fail the test

65. The professor told Baines the result of the test by tossing a coin because     .

 A. he hadn't marked all the papers yet  

B. he couldn't remember the mark Baines got

 C. he wouldn't hurt Baines' feeling by telling him the truth

 D. he wanted to teach Baines a lesson

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