The common cold is the world’s most widespread illness,which is probably why there are more myths about it than any of the other illnesses.
The most widespread mistake of all is that colds are caused by cold. They are not. They are caused by viruses passing on from person to person. You catch a cold by coming into contact，directly or indirectly, with someone who already has one. If cold causes colds, it would be reasonable to expect the Eskimos to suffer from them forever. But they do not. And in distant and isolated Arctic regions explorers have reposed being free from colds until coming into contact again with infected(感染的)people from the outside world by way of packages and mail dropped from airplanes．
At the Common Cold Research Unit in England, volunteers took part in experiments in which they gave themselves to the discomforts of being cold and wet for long periods of time．After taking hot baths，they put on bathing suits，allowed themselves to be doused(浸入)with cold water, and then stood about dripping wet in drafty(通风的)room. Some wore wet socks all day while others exercised in the rain until close to complete tiredness. Not one of the volunteers came down with a cold unless a cold virus was actually dropped in his nose．
If,then,cold and wet have nothing to do with catching colds,why are they more frequent in the winter? Despite the most pains--taking research，no one has yet found the answer. One explanation offered by scientists is that people are more likely to stay together indoors in cold weather than at other times, and this makes it easier for cold viruses to be passed on．
No one has yet found a cure for the cold. There are drugs and pain suppressors(止痛片) such as aspirin,but all they do is to relieve the symptoms．
29. The fact that the Eskimos don’t suffer colds shows that _____.
A. colds are really full of myths. B. viruses are the factors causing colds.
C. colds are more serious than other illnesses. D. the idea that cold leads to colds doesn’t stand up.
30. The experiments mentioned in Paragraph 3 made it clear that _____.
A. it was viruses not wet and cold that made people have colds.
B. taking hot baths made the volunteers easy to be tired.
C. being doused with cold water did harm to one’s body.
D. people who would like to exercise in the rain got colds more easily.
31. According to the passage, colds are commonly seen in winter because _____.
A. staying together indoors makes it easier for viruses to pass on.
B. viruses can go into people’s warm bodies more easily in winter.
C. there is great difference between indoor and outdoor temperature.
D. People are usually weak because of the extreme cold in winter
32. The passage mainly discusses_____.
A. the experiments on colds. B. the myths about colds.
C. the reason and the way people catch colds. D. the continued spread of common colds.