2013年职称英语卫生类B级阅读判断练习题二_第2页

　　41 According to the passage， a greenhouse is built to

　　A keep the plants warm.

　　B prevent air pollution.

　　C stop the greenhouse effect.

　　D produce useful gases.

　　42 Without the greenhouse gases， the earth would

　　A become warmer.

　　B be much colder.

　　C move more slowly.

　　D move quickly.

　　43 A major cause of the increase in the greenhouse gases is

　　A the burning of trees and crops.

　　B the building of many greenhouses.

　　C the burning of large quantities Of coal and oil.

　　D the flooding of large areas of the world.

　　44 According to the passage， chlorofluorocarbon gases differ from carbon dioxide in that

　　A they are more useful.

　　B they are much heavier.

　　C they are more efficient in making the' world colder.

　　D they are more effective in catching the heat from the sun.

　　45 A small increase in the earth's temperature may bring about

　　A a decline in agriculture.

　　B a drop of the sea level.

　　C the death of all animals.

　　D a delay in the greenhouse effect.

　　正确答案：41. A　　42. B　　43. C　　44. D　　45. A