（15）对于四面体ABCD，下列命题正确的是_________（写出所有正

【名词&注释】

四面体(tetrahedron)

[填空题]（15）对于四面体ABCD，下列命题正确的是_________（写出所有正确命题的编号）。

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学习资料：

[单选题]

A. disappointed
B. worried
C. honoured
D. delighted

[单选题]This text is most probably taken from_

A. a research paper
B. a newspaper report
C. a class presentation
D. a geography textbook.

[单选题]The children loved their day trip, and they enjoyed the horse ride .

A. most
B. more
C. less
D. little

[单选题]根据内容，回答下面问题：We have met the enemy, and he is ours. We bought him at a pet shop. When monkey-pox, a disease usually found in the African rain forest, suddenly turns up in children in the American Midwest, it’s hard not to wonder if the disease that comes from foreign animals is homing in on human beings.“Most of the infections(感染)we think of as human infections started in other animals.”says Stephen Morse, director of the Center for Public Health Preparedness at Columbia University.It’s not just that we’re going to where the animals are; we’re also bringing them closer to us. Popular foreign pets have brought a whole new disease to this country. A strange illness killed Isaksen’s pets, and she now thinks that keeping foreign pets is a bad idea.“I don’t think it’s fair to have them as pets when we have such a limited knowledge of them,”says Isaksen.

A. “Laws allowing these animals to be brought in from deep forest areas without stricter control need changing,”says Peter Schantz. Monkey-pox may be the wake-up call. Researchers believe infected animals may infect their owners. We know very little about these new diseases. A new bug(病毒)may be kind at first. But some strains(变异体)may become harmful. Monkey-pox doesn’t look a major infectious disease. But it is not impossible to pass the disease from person to person.
B. 第9题：We learn from Paragraph I that the pet sold at the shop may____ .
C. come from Columbia
D. enjoy being with children
E. prevent us from being infected
F. suffer from monkey-pox

[单选题]—Hi, Tom. Any idea where Jane is? —She_____in the classroom. I saw her there just now.

A. shall be B． should have been
B. must be D． might have been

[单选题]DScience can't explain the power of pets, but many studies have shown that the company of pets can help lower blood pressure (血压) and raise chances of recovering from a heart attack, reduce loneliness and spread all-round good cheer. Any owner will tall you how much joy a pet brings. For some, an animal provides more comfort than a husband/wife. A 2002 study by Karen Allen of the State University of New York measured stress (紧张) levels and blood pressure in people - half of them pet owners –while they performed 5 minutes of mental arithmetic (算术) or held a hand in ice water. Subjects completed the tasks alone, with a husband/wife, a close friend or with a pet. People with pets did it best. Those tested with their ani mal friends had smaller change in blood pressure and returned most quickly to baseline heart rates. With pets in the room, people also made fewer math mistakes than when doing in front of other companions. It seems people feel more relaxed (放松)around pets, says Allen, who thinks it may be because pets don't judge. A study reported last fall suggests that having a pet dog not only raises your spirits but may also have an effect on your eating habits. Researchers at Northwestern Memorial Hospital spent a year studying 36 fat people and their equally fat dogs on diet-and-exercise programs; a separate group of 56 people without pets were put on a diet program. On average, people lost about I1 pounds, or 5% of their body weight. Their dogs did even better, losing an average of 12 pounds, more than 15% of their body weight. Dog owners didn't lose any more weight than those without dogs but, say researchers, got more exercise overall-mostly with their dogs - and found it worth doing.

A. What does the text mainly discuss?
B. What pets bring to their owners.
C. How pets help people calm down.
D. People's opinions of keeping pets.
E. Pet's value in medical research.

[单选题]34________

A. reminded
B. guaranteed
C. convinced
D. promised

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