题目内容

【题目】No sooner __________ the office than __________ his computer to check his e-mails.

A. had he entered; did he started

B. had he entered; he started

C. he had entered; did he started

D. he had entered; he started

【答案】B

【解析】句意:他一走进办公室,就开始查收他的电子邮件。No sooner...than...在句首,主句用倒装;且主句用过去完成时,从句用一般过去时。

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【题目】

Of all the reasons, cloning for medical purposes has the most potential to benefit large numbers of people. How might cloning be used in medicine?

Much of what researchers learn about human disease comes from studying animal models such as mice. Often, animal models are genetically engineered to carry disease-causing mutations (变异) in their genes. Creating these transgenic animals is a time-intensive process that requires trial-and-error and several generations of breeding. Cloning technologies might reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study.

Stem cells are the body's building blocks, responsible for developing, maintaining and repairing the body throughout life. As a result, they might be used to repair damaged or diseased organs and tissues. Researchers are currently looking toward cloning as a way to create genetically defined human stem cells for research and medical purposes. To see how this is done, see Creating Stem Cells for Research, a component of the Stem Cells in the Spotlight module.

Farm animals such as cows, sheep and goats are currently being genetically engineered to produce drugs or proteins that are useful in medicine. Just like creating animal models of disease, cloning might be a faster way to produce large herds of genetically engineered animals. Find out more about this research in the feature article Pharming for Farmaceuticals.

Have you seen Jurassic Park? In this feature film, scientists use DNA preserved for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and fiercer than expected.

In reality? Probably not. It's not likely that dinosaur DNA could survive undamaged for such a long time. However, scientists have tried to clone species that became extinct more recently, using DNA from well-preserved tissue samples.

To clone or not to clone: that is the question. The prospect of cloning humans is highly controversial and raises a number of ethical, legal and social challenges that need to be considered.

【1】 Of all the reason of cloning, which do people think is the most benefit to people?

A. Medicine purpose. B. protecting endangered animal

C. Cloning for some families. D. Purifying human beings

【2】 By the passage we can infer that the side effect people would research human disease using animal models is __________.

A. the sample is not the same with human

B. the sample has less function than human

C. the sample often carries disease in the genes

D. the results can't adapt to human

【3】 What function do stem cells play in body?

A. Breeding. B. Repairing. C. Replacing. D. Reproducing.

【4】 According to the passage, which statement of the following is not right?

A. Cloning animals have achieved now.

B. By cloning people can cure some deadly diseases.

C. Dinosaurs in the future film are smarter.

D. Cloning can bring human only happiness.

【5】 The title of this passage probably is __________.

A. Why clone? B. The benefit of cloning.

C. Cloned animals. D. Cloning in the future.

【题目】We know that cigarette smoking killsSo, producers made electronic cigarettes as a safer smoking choice - safer than tobaccoAlthough e-cigarettes contain the drug nicotine like cigarettes, they do not use tobacco and you do not light themThey are powered by battery (电池).

However, if e-cigarettes are so safe, why has the United States Center for Disease ControlCDCseen an increase in telephone calls about e-cigarette poisonings?

The answer is childrenMost of the calls are from people worried about children who have played with the devices, In the period of one month this year, the Center said 215 people called the Center with e-cigarette concernsMore than half of these calls were for children aged five and youngerThe devices had made them sick

Tim McAfee is director of the Center's Office on Smoking and Health, He says the problem is regulationMeaning, the USfederal government does not control e-cigarettes even though they contain liquid nicotineMrMcAfee adds that liquid nicotine is a well-known dangerMrMcAfee explains that nicotine poisoning happens when it gets into the skin, gets into the eyes or is swallowedIt can cause stomach pain or a sense of unbalanceAnd too much nicotine can kill,

Tim McAfee says e-cigarettes do not create the level of risk to people that tobacco products doHe notes that almost 500,000 Americans die each year from cigarettes"So, cigarettes are the winner in that contest" E-cigarettes do not contain hundreds of harmful chemicals that are found in real cigarettesSo, the USSurgeon General Boris DLushniak has suggested that e-cigarettes may be a useful tool for adults trying to end their tobacco use

But McAfee worries that teenagers may think electronic cigarettes are harmlessThey could become addicted to the nicotine and then start smoking real cigarettesIn other words, he fears that for young people fake e-cigarettes could be a "gateway" to the real thing

1It can be inferred from the passage that______

Athe CDC wants to develop a better type of e-cigarettes

Bthe government is in favor of the use of e-cigarettes

CSurgeon General Boris DLushniak is a heavy smoker

Dsmokers most probably can't quit smoking using e-cigarettes

2What is Tim McAfee's opinion about smoking?

AAdults should use harmless e-cigarettes

BSmoking e-cigarettes can make a person sick

CHe claims that regulations should be made to ban smoking

DHe is concerned about the teens using e-cigarettes

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