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Five cloned pigs，whose organs are much less likely to be rejected(排斥) by a patient，have been born in the U．S.

More than 62,000 people in the U．S. alone are waiting to ____ donated hearts，lungs and so on.The number of human donors falls far short of ____.Pig organs are of a(n) ____ size to human organs，and some scientists hope they might be used to help meet the ____.But previous attempts to transplant pig tissue into humans have ____.

The five pigs ____ a gene that adds a sugar to the surface of pig cells.The sugar would ____ immune(免疫的) rejection of the tissue.“This advance provides a near?time ____ for overcoming the problem that there is not enough human organs for transplants，”says an expert.“This is the ____ gene for overcoming the ____ stage of rejection.”

____，scientists warn that much more work is necessary ____ organs from copies of the pigs could be transplanted into humans.Human genes will need to be added，to ____ rejection of the organ in the long term.There are also ____ that pig viruses could infect patients.

Cloning techniques were ____ to the production of the pigs.Genes can only be knocked out(去除) in a single cell.Cloning of these single cells then allowed the ____ of a whole animal in which the gene was knocked out in every cell.But the PPL researchers have ____ in knocking out only one copy of the gene.The team will now attempt to knock out both copies of the gene.

The team will also ____ tests to investigate whether a virus from the pigs could infect human cells.“Although a lot of the work is very ____，we’re still very far off being able to grow an organ，” says Julia，who is working on this project and quite ____ to creating similar knock?out pigs with researchers at the University of Missouri.

1.A.exchange? B．check

C．possess? D．receive

2.A.discussion? B．demand

C．doubt? D．distance

3.A.beneficial? B．identical

C．similar? D．certain

4.A.shortage? B．condition

C．satisfaction? D．argument

5.A.continued? B．failed

C．finished? D．paused

6.A.lack? B．include

C．make? D．change

7.A.leave? B．cause

C．block? D．destroy

8.A.supply? B．ambition

C．contribution? D．solution

9.A.only B．rare

C．key? D．safe

10.A.last? B．whole

C．next? D．early

11.A.However? B．Therefore

C．Besides? D．Finally

12.A.because? B．before

C．if? D．after

13.A.prevent B．ignore

C．judge? D．weaken

14.A.regrets? B．emotions

C．concerns? D．interests

15.A.simple? B．vital

C．unusual? D．basic

16.A.collection? B．application

C．reception? D．creation

17.A.delighted? B．succeeded

C．joined? D．believed

18.A.conduct? B．plan

C．design? D．study

19.A.perfect? B．strange

C．exciting? D．disappointing

20.A.opposed? B．used

C．devoted? D．suited

Tears slid down Ken's cheeks. Their newbom baby        was removed from life supprt, taken back to her and her  , Charlie. who held their baby. Austin was bom at 12:17 p.m. three months   than he should have been. The length of a school ruler. he weighed one pound. nine ounces. Doctors tried   that technology and medicine could offer at the      baby, but Austin did not respond well. Austin's lung tissue (組織) had probably   　 developing four weeks before. even still     . his mother, because of an accident Zero chance of     . It was time to let him go, and let him leave in his mother's arms － at peace and in no pain.

     In the next few hours, Charlie's parents, and Ken's mother came to meet and say    Austin. Charlie and Keri        their eyes on the baby as he snuggled(依偎) into Keri's chest. The end, they believed. was coming 　 . Nurse Melissa walked in every so often to check Austin's         . If it was time for him t0       . his heart rate would begin to slow. After four hours,     , Austin was still breathing. His heart thumped(跳動) at a healthy 120 beats per       . He moved his head and wrapped his fingers and toes around the fingers of his          . Four hours became five, then six. Austin and his parents remained still     . Word about this baby had spread out. Everyone was talking about him. As the minutes and hours ticked away, Austin was going strong The tests showed a(n)      level of carbon dioxide in his blood. which meant he was        enough oxygen into his body. The clock passed midnight. Austin had        the next day. Miracle. a life miracle!

1.A. Melissa        B. Charlie           C. Austin              D. Keri

2.A. husband       B. nurse             C. doctor              D. wife

3.A. sooner        B. faster             C. later                D. earlier

4.A. something     B. anything           C. everything          D. nothing

5.A. young        B. tiny               C. big                D. sick

6.A. started       B. stopped             C. delayed            D. continued

7.A. inside       B. outside             C. beside              D. with

8.A. arrival       B. approval            C. death               D. survival

9.A. hello to      B. sorry to            C. goodbye to           D. yes to

10.A. put         B. focused            C. took                D. had

11.A. steadily     B. fast               C. slowly               D. soon

12.A. heartbeat    B. mouth             C. blood                D. temperature

13.A. wash       B. live               C. die                  D. eat

14.A. however    B. therefore           C. meanwhile           D. otherwise

15.A. second          B. minute              C. hour               D. day

16.A. friends         B. sisters               C. relatives            D. parents

17.A. crying          B. waiting              C. sitting              D. sleeping

18.A. unsatisfied      B. unacceptable          C. normal             D. excellent

19.A. losing         B. getting               C. making              D. pouring

20.A. lived into      B. waked up             C. waited for            D. suffered from

It was a cold night in December. Two beggars were sitting on a busy street corner in the downtown section of the city. The cold wind made them huddle (擠) together for heat and comfort. They watched helplessly as scores of people walked by, some ignoring them on purpose and others too caught up in their own cares to even notice their existence. Every so often, a kind-hearted woman or a small child would drop a few coins in the hats which lay in front of them on the icy sidewalk. Some people, feeling particularly generous, would even pull out a bill or two from their wallets and drop them into the beggars’ hats and then continued their walking.

Today was not a bad day for begging. The men were able to collect enough for a good meal at the coffee shop down the street and a few candles to light up their shelter in the alley (胡同) behind the train station. As the crowd began to die down, they started to pack up their bundles and head for their evening shelter.

Just as they were getting ready to leave the street corner, they noticed a man walking toward them. He was obviously a wealthy man — they could tell that from the finely tailored business suit he was wearing and the gold watch chain adorned (裝飾) his left pocket.

The first beggar looked at the second and whispered with excitement, “He’s coming our way!

The two tried not to look directly at the man as he stepped closer to them, but they couldn’t help staring at him as he reached into his pocket and took something out.

“Thunk” was the only sound they heard as what looked like a piece of hard candy, wrapped carefully in tissue paper hit each of their waiting hats. The rich man turned and continued on his way, not making a backward glance.

“How insulting!” said the first beggar, as soon as the rich man was out of sight. “He could have easily left us a few coins or a spare bill, but he played a joke on us with a piece of rock candy.”

He looked at the wrapped offering with disgust. “Who does he think we are — children? There’s no way we can even eat this — we have no teeth.”

The beggar picked up the object with the very tips of his fingers and threw it into the gutter (排水溝). He watched as it floated a few yards in the stream of muddy water and disappeared into the gutter at the end of the street. Then, he gathered up his things and walked away.

The second beggar looked down at the morsel in his hat, then at his departing friend. His first thought was to toss the donation in the trash can under the street light. But his second thought made him change his mind.

“I haven’t had anything like this for ages,” he thought. “I can’t chew it, but I can suck on it for a while, and the sweet juice will stay in my mouth for a long time. How nice of that man to offer me something so sweet!”

He opened the paper eagerly, then paused as his hands touched the inside. “Maybe I should save it for another time,” he thought. “It won’t spoil, and I could eat it later when I’m really hungry.”

The beggar paused for a moment, then he said aloud, “He wanted me to have it anyway. I might as well enjoy it now.”

With that, he unfolded the paper, but to his surprise, there was no hard rock candy inside. Instead, into his fingers fell a shiny white pearl worth thousands of dollars.

55. The first paragraph serves as a(n) ______.

A. explanation 　　　　B. introduction 　　C. background 　　 D. comment

56. The two beggars started to leave the street corner when ____.

A. darkness fell 　　　　　　　　 B. few people passed by

C. they felt too cold 　　　　　　　D. the wind began to blow hard.

57. The two beggars thought the man was rich from _____.

A. his appearance 　　　　　　　B. his way of walking

C. the jewellery he wore 　　　　　D. the shiny shoes

58. What did the first beggar think of the rich man?

A. He looked down upon the poor. 　B. He was very kind and warm-hearted

C. He treated them as children D. He was too mean.

59. The underlined words “the morsel in his hat” probably refer to ______.

A. the donation from the rich man

B. the coins the second beggar collected

C. the rock candy the rich man gave the second beggar

D. the food the second beggar left over

60. What can we learn from the story?

A. Every dog has its day.

B. Patience is the best remedy for every trouble.

C. He who laughs last laughs best.

D. He that can have patience can have what he will.