An English man was talking with the desk clerk（公务员）at the New York Hilton.
"Here is a riddle（谜语），"said the clerk."My mother gave birth to a child.It was neither my brother nor my sister.Who was it？"I can't guess."said the Englishman."It was me，"laughed the clerk."Ha！Ha！Very clever.I must remember that，"said the Englishman with a smile Later，the Englishman tried the riddle on his friend."Here is a riddle，my dear.My mother gave birth to a child who was neither my brother nor my sister.Who was it？"His friend began to think.Then he said，"Do you give up？""Yes"“It was the desk clerk at the New York Hilton."