单选题On September 2, 1937, President Roosevelt signed legislation that was to have far-reaching consequences for American wildlife.

单选题Many Europeans ______ the continent of Africa in the nineteenth century.

单选题The newly employed waitress, a pretty young woman, slapped the manager on the cheek when he tried to kiss her.

单选题(The age of) a geological sample can (be estimated) from the ratio of radioactive to nonradioactive carbon (present) in the object (is examined).A. The age ofB. be estimatedC. presentD. is examined

单选题______ , the house was a good buy.

单选题One of the main reasons is that the university's______attracts students and faculty staff all over the world.

单选题Although it seemed to take all her strength ,the patient ______ up a smile to her morn.

单选题(The) great American supermarket is a wonderful place with (the) great variety of (healthy food) and (other commodities).

单选题It is very interesting that many language teachers are ______ to talk too much at home as well as in class.

单选题Woman: Tim, why don't you like Sue? She seems to be a very good girl.Man: A very good girl? She always has her nose in the air.Question: Why doesn't Tim like Sue?

单选题{{B}}Passage Four{{/B}} We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals too. In one experiment, for example, behavioral immunologist (免疫学家) Mark Laudenslager, at the University of Denver, gave mild electric shocks to 24 rats. Half the animals could switch off the current by turning a wheel in their enclosure, while the other half could not. The rats in the two groups were paired so that each time one rat turned the wheel it protected both itself and its helpless Partner from the shock. Laudenslager found that the immune response was depressed below normal in the helpless rats but not in those that could turn off the electricity. What he has demonstrated, he believes, is that lack of control over an event, not the experience itself, is what wakens the immune system. Other researchers agree, Jay Weiss, a psychologist at Duke University School of Medicine, has shown that animals who are allowed to control unpleasant stimuli don't develop sleep disturbances or changes in brain chemistry typical of stressed rats. But if the animals are conditioned to confront with situations they have no control over, they later behave passively even when faced with experiences they can control. Such findings reinforce psychologists' suspicions that the experience or perception of helplessness is one of the most harmful factors in depression. One of the most startling examples of how the mind can alter the immune response was discovered by chance. In 1975 psychologist Robert Ader at the University of Rochester School of Medicine conditioned (使形成条件反射) mice to avoid saccharin (糖精) by simultaneously feeding them the sweetener and injecting them with a drug that while suppressing their immune systems caused stomach upsets. Associating the saccharin with the stomach pains, the mice quickly learned to avoid the sweetener. In order to extinguish this dislike for the sweetener, Ader reexposed the animals to saccharin, this time without the drug, and was astonished to find that those mice that had received the highest amounts of sweetener during their earlier conditioning died. He could only speculate that he had so successfully conditioned the rats that saccharin alone now served to weaken their immune systems enough to kill them.

单选题A: Could you change these pounds for dollars, please?B: ______

单选题{{B}}Passage Four{{/B}} Still happily together, Mayer Solen and Joann Oakes credit Senior-Net for "introducing" them not only to each other but also to a world of computer-literate over-60 s. "Senior-Net offers a forum where senior citizens can talk freely, help each other, and even console each other,"Joann says. "Even though we are scattered across the country, we can share thoughts, opinions and concerns about issues that affect us. It's like a big family. When Mayer and I travel around the country, we make it a point to look up other Senior-Net members." Mary Furlong, founder of the 10-years-old network, says it is a painless way to socialize, especially for those recently widowed and reluctant to go out alone, and for the disabled. Senior-Net has more then 6 000 members across the United States. Joann Oakes and Mayer Solen fell for each other just before Christmas in 1991. She had been watching from a distance as Mr. Solen flitted from one group of friends to another. Finally, the two began a conversation. They discovered they were both widowed. They talked on and on. At midnight, they said good night, turned off their computers and went to bed, Mr. Solen in the south-western state of Nevada, and Mrs. Oakes in the north-western state of Washington. From then on they talked nearly every day via their computers until their marriage. Computers are playing Cupid for what seems to be an unlikely target—a generation that didn't know the difference between a mouse and a modem until they reached 60. Now, older adults are plugged in to exchange gardening tips, debate religion ,or try to recall the lines of old time popular songs. The marriage between seniors and computers is, in fact, perfectly natural. They grew up in a time when people wrote weekly letters to each other and kept journals and diaries. A computer is an easier way to do the same. With no risk of censure or rejection, grandfathers can let their hair down. Church-going people confess they are not really sure what they think about religion. People who always thought of themselves as conserved and "respectable" may be found flirting shamelessly with correspondents who live 500 miles away. If anyone dislikes the company or the discussion, they don't have to be polite. "Just hit the control button and you're gone," says Joann Oakes.

单选题He ______ his letter of application to the director of the Personnel Department of that company.

单选题Woman: You are too careful. I can hardly put up with a car moving at this speed. Man: Once bitten twice shy. I was involved in a head-on collision a few months ago. I don't want to repeat it. Question: What can we learn from the conversation?

单选题A: Bob, would you mind turning down the TV a little? I'm talking on the phone, and I'm having a hard time hearing. B: ______

单选题There's the fear that parents might clone a child to have " spare parts" ______ an organ transplant is needed.