----This returned Chinese scholar has become one of the top experts in this field.

----Yes,I know him very well.He____in Africa with animals for eight years.

A、has worke B、had worked C、worked D、has been working

-- He was given a free five-day trip to Hainan.
-- He _______ it since he has worked so hard.

He has thrown away his old shoes.He’ll have to buy ____.

        A. a new one   B. a new pair    C.some new pair     D. a new shoes

Researchers are placing robotic dogs（机器狗）in the homes of lonely old people to determine whether they can improve the quality of life for humans. Alan Beck, an expert in human-animal relationship, and Nancy Edwards, a professor of nursing, are leading the physical activity, and life satisfaction. “No one will argue that an older person is better off being more active, challenged, or stimulated（刺激）,” Edwards points out. “The problem is how we promote（使……成为现实）that, especially for those without friends or help. A robotic dog could be a solution.”

In the study, the robot, called AIBO, is placed for six weeks in the houses of some old people who live alone. Before placing AIBO in the home, researchers will collect baseline data for six weeks. These old people will keep a diary to note their feelings and activity before and after AIBO. Then, the researchers will review the data to determine if it has inspired any changes in the life of its owner.

“I talk to him all the time, and he responds to my voice,” says a seventy-year-old lady. “When I’m watching TV. he’ll stay in my arms until he wants down. He has a mind of his own.”

The AIBOs respond to certain orders. The researchers say they have some advantages over live dogs, especially for old people. Often the elderly are disabled and cannot care for an animal by walking it or playing with it . A robotic dog removes exercise and feeding concerns.

“At the beginning, it was believed that no one would relate to the robotic dog, because it was metal and not furry, ”Beck says. “But it’s amazing how quickly we have given up that belief.”

“Hopefully, down the road, these robotic pets could become a more-valuable health helper. They will record their masters’ blood pressure. oxygen levels, or heart rhythms. AIBOs may even one day have games that can help stimulate older people’s minds. ”

48．The purpose of Beck and Edwards’ study is to ______.

       A．understand human-animal relationship

       B．make lonely old people’s life better

       C．find the causes of old people’s loneliness

       D．promote the animal-assisted research

49．In the research, the old people are asked to ______.

       A．note the activities of AIBOs

       B．keep AIBOs at home for 12 weeks

       C．record their feelings and activity

       D．analyze the collected information

50．What is the advantage of AIBO over live dogs?

         A．It is easier to keep at home.

         B．It can help the disabled people/

         C．It responds to all the human order.

         D．It can watch TV with its owner.

51．The author seems to suggest that the future robotic dogs may ________.

         A．cure certain diseases

         B．keep old people active

         C．change people’s beliefs

         D．look more like real dogs

 He is _______ every day. He has never been late for school.

A. busy                        B. diligent            C. careful                     D. punctual