Everyone knows what happens when you catch a cold.First you

Everyone knows what happens when you catch a cold.First you get a sore (疼痛的) throat.Then you sneeze (打喷嚏).After coughing and blowing your way through the next few days,it's over...until the next time.
Every year 69% of Canadians will suffer at least one cold.Colds are responsible for a great deal of lost time at work and at school.
There is no known cure for the common cold.Once you catch a cold,your body usually makes antibodies (抗体) against the virus.These antibodies help the body develop a resistance (抵抗力) to the virus if you catch it again.Unfortunately,the common cold is caused by over 200 different viruses.The large number of viruses and the fact that they change help explain why there is no cure for the common cold.Adults,who have been exposed (遭受) to more viruses,tend to suffer fewer colds than children.
The occurrence of colds tends to increase in the winter but NOT because of the cold!Cold weather has not been shown to increase the number of colds.People spend more time indoors in winter.They are therefore more likely to come into physical contact with each other and spread the disease.
Common colds are spread by sneezes or by direct contact with a cold sufferer.Sneezing spreads colds when someone sneezes near other people,or sneezes on objects which others later touch.Once the virus is on someone's hand,and the unsuspecting (毫无戒心的) victim touches his or her nose or eyes,the virus is spread and trouble begins.
The simplest and most effective way to lower the risk of catching a cold is to wash your hands frequently.
6.At the very beginning of the passage,the writer talks about ________.A.what a cold is likeB.what a cold virus is likeC.how to cure a coldD.how to prevent a cold from spreading7.There is no cure for the common cold because ________.A.the nature of colds remains unknownB.the large number of cold viruses keeps changingC.your body can't develop antibodiesD.your resistance isn't strong enough8.Which of the following products would have increased sales if more people became aware of the real reason for the spread of colds?A.Sweaters (毛衣).B.Paper napkins (餐巾).C.Soap.D.Bottles of water.9.People are more likely to catch a cold if they ________.A.go outside in the cold winterB.talk to those who once had coldsC.often wash their handsD.always stay indoors and have physical contact with each other10.Colds are spread by ________.A.sneezesB.direct contacts with a cold suffererC.touching objects with virusesD.All of the above.

A B C B D