职称英语考试理工类阅读理解专项训练(4)

　　Where Have Allthe Bees Gone 　　Scientists who study insects have a real mystery on theirhands.All across the country，honeybees are leaving their hives and neverreturning. Researchers call this phenomenon colony-collapse1 disorder.Accordingto surveys of beekeepers across the country，25 to 40 percent of the honeybeesin the United States have vanished from their hives since last fall.So far，noone can explain why. 　　Now，a group of scientists andbeekeepers have teamed up to try to figure out whats causing the alarmingcollapse of so many colonies. By sharing their expertise in honeybee behavior，health，and nutrition，team members hope to find out whats contributingto thedecline and to prevent bee disappearance in the future. 　　Another cause of colony-collapse disorder may be certain chemicalsthat farmers apply to kill unwanted insects on crops，says Jerry Hayes，chief beeinspector for the Florida Department of Agriculture3.Some studies，hesays，suggest that a certain type of insecticide affects the honeybees nervoussystem and memory.It seems tike honeybees are goingout and getting confused about where to go and what to do, he says. 　　练习： 　　1. What is the mystery that researchers find hard to explain? 　　B 25-40 percent of the honeybees inthe US have died. 　　D Honeybee hives are in disorder. 　　A Because honeybees produce one-third of the foods we eat. 　　C Because honeybees eat seeds of flowers. 　　3. What are the possible causes of colony-collapsedisorder given by the scientists? 　　B Diseaseand chemicals. 　　D Changes ingenes structures. 　　A Bees genes allow them toexpand their colonies. 　　C Beesgenes make them fly from flower to flower. 　　5. What explanation is given byJerry Hayes to the phenomenon? 　　B The insecticide destroys the honeybees nervous system. 　　D All of theabove.