职称英语真题理工2008年B类：阅读理解_职称英语考试真题理工类

职称英语真题理工2008年B类：阅读理解

　　35 In the last paragraph the word persistent means

　　A important. B effective. C enduring. D visible.

　　第二篇 Where Have All the Bees Gone?

　　Scientists who study insects have a real mystery on their hands.All across the country, honeybees are leaving their hives(蜂巢)and never returning.Researchers call this phenomenon colony-collapse(群体瘫痪)disorder.It is reported that 25 to 40 percent of the honeybees in the US have vanished from their hives since last fall.So far, no one can explain why.

　　Colony collapse is a serious concern because bees play an important role in the production of about one-third of the foods we eat.As they feed，honeybees spread pollen(花粉)from flower to flower.Without this process，a plant cant produce seeds or fruits.

　　Now，a group of scientists and beekeepers have teamed up to try to figure out whats causing the alarming collapse of so many colonies.They hope to find out whats contributing to the decline and to prevent bee disappearance in the future.

　　It could be that disease is causing the disappearance of the bees.To explore that possibility，Jay Evans，a researcher at the United States Department of Agriculture(USDA)Bee Research Laboratory, examines bees taken from colonies that are collapsing. We know what a healthy bee should look like on the inside, and we can look for physical signs of disease,he says.And bees from collapsing colonies dont look very healthy. Their stomachs are worn down, compared to the stomachs of healthy bees,Evans says.It may be that a parasite(寄生虫)is damaging the bees digestive organs.Their immune(免疫的) systems may not be working as they should.Moreover, they have high levels of bacteria inside their bodies.