Dr. Jack M. Gwaltney, Jr. a professor at the University Of Virginia School Of Medicine infected six student volunteers with virus, the most common cause of colds. A few days later, when they were coughing and sneezing, he gathered 37 more people and divided them into three groups. Group 1 members spent three days and nights in the same room with one of the infected students, separated by a screen so they couldn't touch one another. Group 2 sat around a table while an infected volunteer talked, coughed and sang to them. Group 3 held hands with an infected student for ten seconds, and then touched their own noses or eyes.
Although most scientists at the time, the mid-70s, believed colds were spread by virus-laden droplets spread through the air when infected people coughed or sneezed, Gwaltney suspected physical contact might play an important role. Sure enough, of the 15 people who had touched a student volunteer, 11 became infected—compared with only one of those who had been sitting at the table, and none who had spent three days and nights together.
"The best evidence we have is that hand-to-hand contact is the most efficient way of transmitting virus," says Gwaltney. The study was one of a series that helped establish Gwaltney's reputation as a leading authority. Dr. Robert Couch says, "It would not be inappropriate to call him Mr. Common Cold."
When Gwaltney is asked how close scientists are to finding a cure, he replies: "If you mean ‘get rid of’, I don't think we're going to be able to do that with cold viruses any time soon. But if you look in the dictionary, you'll see that 'cure' is explained as a successful treatment. And we're not just getting more effective at treating the symptoms (症状)—we're getting at the root cause too. "
【小题1】Dr. Jack M. Gwaltney conducted the experiment in order to__________.

The poorer mental function seen among alcoholics，many of whom also regularly smoke cigarettes，may be partly due to the long term effects of nicotine(尼古丁)，new research suggests.
“People who are also smokers are at a much higher risk，” Dr.Jennifer  M.Glass of the University of Michigan's Addiction Research Center said. In her study，“Cigarette smoking has a bad effect on IQ and thinking，” she said.
This finding may seem counterintuitive(违反直觉的)，since many smokers show that they feel quicker and focused after smoking. Indeed，research shows that improved mental functioning is one of the immediate effects of nicotine exposure. Chronic(慢性的)smoking，however，is known to have the opposite effect. Studies show that up to 87 percent of alcoholics smoke cigarettes.
Yet，few studies have looked into cigarette smoking as a factor that might explain the cognitive(认知的)lack reported among alcoholics. To search for that association，Glass and her colleagues examined brain function among 172 men from the same area，including 103 men who abused alcohol. The team found that men with higher scores on the lifetime alcohol problems scale(LAPS)and those who reported a higher number of pack years of smoking both had lower IQ scores.
Upon further research，the researchers found that smoking also appeared to be independently associated  with weaker word and space reasoning.
Thus，though smoking did not account for all of the decreased mental functioning observed among the alcohol abusers，it did seem to account for some of the effects，the report indicates.
【小题1】What is the passage mainly about?

Directions: Read the following text and choose the most suitable heading from A-F for each paragraph．There is one extra heading which you do not need.

I have heard that fluoride can help stop dental decay, but I recently read that it is poisonous．Which of these is true? How can children use fluoride safely?

This question is answered by Dr Marcia M．Rich who practises general dentistry in Newholt．She is also a lecturer at the University and a writer for the monthly magazine Your Dentist Cares．

My answer to the first question is to stress that fluoride works well and is safe when users follow instructions．Young children have a tendency to swallow toothpaste, which is why they should only have a tiny amount of fluoride toothpaste on their toothbrush．If this simple measure is taken, parents can be confident that children will be protected against tooth decay, and come to no harm.

Almost all medicines have an adverse effect－or even be deadly－if they are not taken as directed．So you are right－fluoride can be poisonous if it is swallowed in very large quantities．It is for the reason that fluoride supplements can only be obtained on prescription from the doctor or dentist．Please be assured that fluoride overdoses are rare－in fact, I have never heard of any fatal incidents related to fluoride poisoning.

Scientific studies have shown that fluoride can help to prevent cavities as long as it is used correctly．If fluoride is abused, there is a risk of illness or even deaths in extreme cases．If a deadly amount of fluoride is taken, immediate first-aid could save a life．A person who has swallowed a large amount of fluoride will probably start vomiting．If not, the patient should be given milk or antacid and taken to the nearest hospital for emergency treatment.

Taking too much fluoride while teeth are growing can lead to a condition called dental fluorosis．The most likely cause is the swallowing of fluoride toothpastes by young children．It can also be caused by inappropriate use of fluoride drop or other fluoride supplements, for example when fluoride is already is already present in drinking water．  

Directions: Read the following text and choose the most suitable heading from A-F for each paragraph．There is one extra heading which you do not need.

第三部分：阅读理解（共15小题;每小题2分，满分30分）

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。

Most people don't know the true story of the little boy who came to be known as Douglas Craig. He was found wandering around the streets of Washington, D.C. He could not hear or speak. At night, he drew the knees up to his body in doorways and slept. Sometimes people pitied him and gave him food and clothing. If not, he ate what he could find in garbage cans.

Dr. E. M. Gallaudet at Gallaudet College let him stay in the Kendall School until he was old enough to work. He became the best "handy man" that Gallaudet had ever had. He had many duties, such as picking up mail at the post office, mowing grass, tending the flower beds, and carrying notes from the boys to the girls. Clearly, he was a familiar sight on campus.

It is said that Douglas courted(求爱) a black woman from Baltimore. Since his courtship required letter-writing, and he was illiterate, he had a student in the college act as his "private secretary." Though that relationship did not work out, he did marry a black deaf woman. The wedding took place in a church, and most of the college faculty and teachers were present. Douglas was dressed in a full-dress suit with a white tie and white gloves. The happy couple went to Baltimore for a honeymoon, but the honeymoon only lasted for one day. Their plans were cut short when his pocketbook containing about $300 was either lost or stolen.

He once went to Norfolk, Virginia on a vacation, but he did not know what a vacation was. He spent the entire time working around the docks of Norfolk. He came home with a pocketful of money, and told everyone that he had a fine vacation.

Douglas' last public duty was to raise the flag to the top of the new flagpole. He was very weak and sat in an armchair during the ceremonies. He died in 1936, but left a legend at Gallaudet that would live forever.

1. The main idea of the story is that_____:

A. Craig liked no women except those from universities.

B. Gallaudet is the best place for an orphan to grow up.

C. No one ever found out exactly what happened to Craig’s family.

D. Craig, a man with an unusual background, worked at Gallaudet for many years.

2. It is most likely that Douglas Craig enjoyed working at Gallaudet because_____:

A. Gallaudet was a good place to collect junk.    B. he found it easy to communicate with people.

C. people felt sorry for him so he didn't have to work hard.     D. he didn't have a home.

3. Craig and his new wife's honeymoon did not last long because_______:

A. their money was lost or stolen.     B. Craig missed Gallaudet and wanted to come back early.

C. they spent all their money.        D. their baggage and clothing was lost or stolen.