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Scientists have found that pesticides (农药) harm the ability of bees to find food. Bees must learn which flowers contain their food from the smells of the flowers.       the bees do not learn which smells mean food, they will starve. Researchers in Britain found that pesticides  (use) by farmers and gardeners can switch off the part of a bee’s brain that is responsible    associating smells with food. Lead researcher Dr. Geraldine Wright said pesticides could seriously impact the      (survive) of honeybee colonies. She said, “Bees that cannot learn will not be able to find food.” This also      (mean) bees will not pollinate (给……授粉) crops and wild plants.
Bee populations around the world have been declining. Scientists have searched for a long time for a reason       so many bees are disappearing. This new research may be     important clue. However, the British government does not want to stop the use of the pesticides that may prevent bees from learning.    wants to carry out more tests to make sure pesticides are the real reason for the decrease in the number of bees. A spokeswoman from the Friends Of The Earth charity said the government must act      (soon) rather than later. “Bee health is far too urgent to wait    more research has been completed. Controls should be placed on these pesticides until bee safety can be guaranteed,” she said.