David Bennett,an American man who received a genetically-modified（转基因的）pig heart in transplant(移植) surgery, died on Tuesday, March 8,2022. The hospital said he was doing well at first after the operation but his condition became worse several days later.

　　Doctors from the University of Maryland Medical Center performed the operation after receiving special agreement from the U.S. government for it. The operation took seven hours.It is the first time that this has happened and proved an animal heart can survive in a human.

　　Before the operation.Mr Bennett was very ill and had spent the last several months in bed on a life support machine. The doctors said giving him the pig's heart was the only chance of keeping him alive.Bennett said to doctors the day before the operation.“It is either to die or to do this transplant. I want to live. I know it's a shot in the dark.but it's my last choice.”

　　Scientists had changed the genes(基因）of the pig so its heart would be more suitable for a transplant into a human. It was performed by firm Revivicor, which also supplied the pig used in a kidney transplant on a brain-dead patient in New York in October.

　　Scientists have been researching pig-organ transplants for years. They said although Mr Bennett died, this still could bring the world one step closer to solving the organ shortage(短缺）problem”.About 110,000 Americans are now waiting for an organ transplant,and more than 6,000 patients die each year before getting one. David Bennett Jr.s said,““We are grateful for every innovative moment, every crazy dream, every sleepless night that went into this historic effort. We are optimistic and believe this story is the beginning of hope and not the end.”

　　1.What can we learn from the first two paragraphs?

　　A. The government supported the operation.

　　B. Doctors did the operation on March8,2022.

　　C. Bennett didn't feel well at first after the operation.

　　D. Bennett's death showed animal hearts can't survive in humans.

　　2.What does the underlined part "a shot in the dark"probably mean?

　　A. A shame.

　　B. An accident.

　　C. An operation.

　　D. A try.

　　3.What did the firm Revivicor do?

　　A. It changed the pig's genes.

　　B. It created a man-made kidney.

　　C.It performed the heart transplant.

　　D. It saved many brain-dead patients.

　　4.Why do scientists research pig-organ transplants according to the text?

　　A.To solve the organ shortage problem.

　　B. To reduce the cost of heart transplants.

　　C. To develop genetically-modified technology.

　　D. To provide a new choice for brain-dead patients.

　　5. Which word can best describe David Bennett Jr.'s attitude(态度）？

　　A. Careless. B. Doubtful.

　　C. Confident. D. Uncertain.
 

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