Nativity scenes traditionally include the Three Wise Men, Balthazar, Melchior, and Caspar, although their names and number are not referred to in the Biblical narrative.

• 在不应期强行加大性刺激，强迫自己再次就是让性系统超负荷工作。美国人做的一个统计，时间越短、质量越差，不应期就越短；