龙门石窟始开凿于北魏孝文帝迁都洛阳（公元493年）前

[align=left][size=12pt]Several weeks after a young man had been hired, he was called into the personnel director's office. [/size][/align][align=left][size=12pt]"What is the meaning of this?" the director asked. "When you applied for the job, you told us you had five years' experience. Now we discover this is the first job you ever held." [/size][/align][align=left][size=12pt]brick machine[/size][/align][align=left][size=12pt]"Well," the young man said, "in your advertisement you said you wanted somebody with imagination." [/size][/align]