collapsing colonies don’t look very healthy.“their stomachs are worn downpared to the stomachs of healthy bees，”‘evans says.it may be that a parasite(寄生虫)making 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.
another cause of colony—collapse disorder may be certain chemicals that farmers apply to kill unwanted insects on crops，says jerry hayes，chief bee inspector for the florida department of agriculture.some studies，he says，suggest that a certain type of insecticide(杀虫剂)affects the honeybee’s newels system and memory.“it seems like honeybees are going out and getting confused about where to go and what to do”he says.
1f it turns out that a disease is contributing to colony collapse，bees’genes could explain why some colonies have collapsed and others have not.in any group of bees there are many different kinds of genes.the more different genes a group has，the higher the group’s genetic diversity.so far scientists haven’t determined the role of genetic diversity in colony collapse，but it's a promising theory，says evans.
36. what is the mystery that researchers find hard to explain?
a. honeybees are flying all across the country.
b. half of the honeybees in the us have died.
c. honeybees are leaving their hives and do not return.
d. honeybee hives are in disorder.
37. researchers are seriously concerned with the phenomenon of colony—collapse disorder because
a. honeybees help produce one-third of the foods we eat
b. parasites on bees may spread everywhere.
c. honeybees cannot find enough food elsewhere.
d. honeybees feed on flowers.
38. which of the following is a possible cause of the colony-collapse disorder?
a. population explosion.
b. decreasing number of flowers around.
c. genetically modified products.
d. diseases and chemicals.
39. which of the following explanations is given by jerry hayes to the phenomenon?
a. bee-keepers do not understand the honeybee’s behavior.
b. a certain type of chemical destroys the honeybee’s newels system.
c. honeybees are infected by unwanted insects.
d. some crops are poisonous to the honeybees.
40. the word “diversity’ in the last paragraph means
a. variety.来源：
b. makeup.
c. disorder.ｅxamda
d. distinction.
第三篇a tale of scottish rural life
lewis grasses gibbon’s sunset song(1932)was voted“the best scottish novel of all time”by scotland’s reading public in 2005.once considered shocking for its frank description of aspects of the lives of scotland’s poor rural farmers，it has been adapted for stage，film。tv and radio in recent decades.
the novel is set on the fictional estate of kin addie，in the farming country of the scottish northwest in the years up to and beyond world war i.at its heart is the story of chris，who is both part of the community and a little outside it.
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