Are you a man or a mouse?When people ask this question they want to know __36_ you think you are a _37_ person or a coward(懦夫).But you will never really know the answer to this question __38__you are tested in real life.Some people __39__they are brave but when they come face to face with real __40_,they act like cowards.Others think of themselves as cowards,but when they meet danger,they act like __41_.Lenny had always thought of himself as a __42__person.He got worried before examinations.He worried about his job and his health.All he wanted in life was to be safe and healthy.__43__,on January 15th,2002,a plane crashed into the Potomac River in Washington.Lenny went to the river to see what was happening.He saw a woman in the __44__water.Lenny did not feel afraid.He kept very __45__and did a very courageous thing.He jumped into Potomac,__46__to the woman,and kept her head __47__the water.Seventy-eight people died that day.Thanks to Lenny,it was not __48__.When you are in a very __49__situation and feel afraid,the body automatically（自动地）produces a chemical in the blood.This chemical is called adrenalin(肾上激素).__50__adrenalin in the blood system,you actually feel stronger and stronger and are __51__to fight or run away.However,when you are absolutely terrified,the body can produce too much adrenalin.When this __52__ ,the muscles become very hard and you find you __53__move at all.You are paralyzed(使无能为力) with fear.This is __54__when we ar