About 200 different strains of virus are capable of producing colds. Frequently two or more different viruses can be isolated during a single episode. The cold is spread by person-to-person contact. People can carry the virus and communicate it without themselves experiencing any of the symptoms. Incubation is short--usually one to four days. The viruses start spreading from an infected person before the symptoms appear, and the spread reaches its peak during the symptomatic phase. The incidence of colds peaks during the autumn, and minor epidemics commonly occur throughout the winter. The reason for this incidence is unknown; it may not stem mainly from stresses imposed by chilly weather but rather result from the greater amount of time spent indoors, which increases the likelihood of close contact with those persons carrying cold viruses.
Pathologic changes occurring in the mucous membrane that lines the nose, the nasal sinuses, the nasoharynx, and other upper respiratory passages may include tissue swelling, congestion of blood, and oozing of fluids. During the acute phase of the disease, the respiratory secretions are altered by increase in serum proteins. Parts of cells may also be found in tile fluids. Tissue repair is rapid and seems complete, although a relationship might exist between colds and more serious respiratory conditions.
Cold symptoms vary from person to person, but in the individual the same symptoms tend to recur in succeeding bouts of infection. Manifestations may include sneezing, headaches, fatigue, chilling, sore throat, inflammation of the nose (rhinitis), and nasal discharge. There is usually no fever. The symptoms usually last for only a few days. The nasal discharge is the first warning. The secretions become watery, clear, and excessive. Later, they thicken, increase in mucus and pus content, and may colour a yellow-green, with traces of blood. Coughing can be dry or produce amounts of mucus. Other more serious diseases with similar general symptoms may be mistaken for a cold; some of these are tuberculosis, bronchitis, lung abscesses, and inflammation around the heart.
Treatment is, in most instances, directed toward allaying of symptoms, coupled with rest and adequate fluid intake. Occasionally antibiotics are given to prevent secondary infections.
The word "recur" in Line 2, Para. 4 most probably means
A.refresh.
B.regress.
C.repeat.
D.retreat.
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One country received its second-place medals with visible indignation after the hockey final. There had been noisy scenes at the end of the hockey match, the losers objecting to the final decisions. They were convinced that one of their goals should not have been disallowed and that their opponents’ victory was unfair. Their manager was in a rage when he said: "This wasn’t hockey. Hockey and the International Hockey Federation are finished." The president of the Federation said later that such behavior could result in the suspension of the team for at least three years.
The American basketball team announced that they would not yield first place to Russia, after a disputable end to their contest. The game had ended in disturbance. It was thought at first that the United States had won by a single point, but it was announced that there were three seconds still to play. A Russian player then threw the ball from one end of the court to the other, and another player popped it into the basket. It was the first time the USA had ever lost an Olympic basketball match. An appeal jury debated the matter for four and a half hours before announcing that the result would stand. The American players then voted not to receive the silver medals.
Incidents of this kind will continue as long as sport is played competitively rather than for the love of the game. The suggestion that athletes should compete as individuals, or in non-national teams, might be too much to hope for. But in the present organization of the Olympics there is far too much that encourages aggressive patriotism.
What conclusion can be drawn from the passage
A.The organization of the Olympic Games must be improved.
B.Athletes should compete as individuals in the Olympic Games.
C.Sport should be played competitively rather than for the love of the game.
D.International contests are liable for misunderstanding between nations.
One country received its second-place medals with visible indignation after the hockey final. There had been noisy scenes at the end of the hockey match, the losers objecting to the final decisions. They were convinced that one of their goals should not have been disallowed and that their opponents’ victory was unfair. Their manager was in a rage when he said: "This wasn’t hockey. Hockey and the International Hockey Federation are finished." The president of the Federation said later that such behavior could result in the suspension of the team for at least three years.
The American basketball team announced that they would not yield first place to Russia, after a disputable end to their contest. The game had ended in disturbance. It was thought at first that the United States had won by a single point, but it was announced that there were three seconds still to play. A Russian player then threw the ball from one end of the court to the other, and another player popped it into the basket. It was the first time the USA had ever lost an Olympic basketball match. An appeal jury debated the matter for four and a half hours before announcing that the result would stand. The American players then voted not to receive the silver medals.
Incidents of this kind will continue as long as sport is played competitively rather than for the love of the game. The suggestion that athletes should compete as individuals, or in non-national teams, might be too much to hope for. But in the present organization of the Olympics there is far too much that encourages aggressive patriotism.
The author gives the two examples in paragraphs 2 and 3 to show
A.how false national pride led to undesirable incidents in international games.
B.that sportsmen have been more obedient than they used to be.
C.that competitiveness in the games discourages international friendship.
D.that unfair decisions are common in Olympic Games.
Now, listen to the news.
Riot police
A.surrounded the Japanese embassy at once.
B.have encountered such protest for two years.
C.were armed with guns and clubs.
D.formed a human barricade to prevent possible violence.
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