nimble       
adjective  usually approving uk/ˈnɪm.bəl/ us/ˈnɪm.bəl/
 (行动)灵活的,敏捷的;(头脑)机敏的,敏锐的
quick and exact either in movement or thoughts
  nimble fingers/feet 灵巧的手指/双脚 
 His nimble mind calculated the answer before I could key the numbers into my computer. 我还没来得及把数字输入计算机,他那敏捷的头脑已经算出了答案。