词汇	response cost
释义	response cost 反应代价
随便看	have a tough time of it have at our disposal have at our finger-ends have at our fingers ends have at our fingertips have a tradition have a trial have a trial of strength have a trick have a trick of have a trick of doing have a trick up your sleeve have a trip have a trip of observation have a troubled look have a trouble in eyesight have a true realization of have a true realization of something Have a try,anyhow.or Suppose you give it a try Have a try, anyhow.or Suppose you give it a try have a try at have a try at it have a try for it have at sb have at someone