Mental deficiency

　　"Would you mind telling me, Doctor," Bob asked ..."how you detect a mental deficiency in somebody who appears completely normal?" "Nothing is easier," he replied. "You ask him a simple question which everyone should answer with no trouble. If he hesitates, that puts you on the track." " Well, What sort of question?" "Well, you might ask him, 'Captain Cook made three trips around the world and died during one of them. Which one?' Bob thought for a moment, and then said with a nervous laugh, "You wouldn't happen to have another example would you? I must confess I don't know much about history."

　　“医生，你能不能告诉我，”鲍勃问，“对于一个看 上去很正常的人，你是怎样判断出他有智力缺陷的呢?”“再没有比这容易的了，”医生回答，“问他一个简单的'问题，简单到所有人都知道答案，如果他回答得不 干脆，那你就知道是怎么回事了。”“那要问什么样的问题呢?”“嗯，你可以这样问，‘库克船长环球旅行了三次，但是在其中一次的途中他去世了，是哪一次 呢?’”鲍勃想了一会儿，紧张的回答道，“你就不能问另外一个问题吗?坦率地说，我对历史了解的不是很多。”