少年不识愁滋味,为赋新词强说愁,而今识尽愁滋味,却道天凉好个秋,为什么?

少年不识愁滋味,为赋新词强说愁,而今识尽愁滋味,却道天凉好个秋,为什么? 少年不识愁滋味,为赋新词强说愁,而今识尽愁滋味,欲说还休,却道天凉好个秋. 少年不识愁滋味爱上层楼.爱上层楼为赋新词强说愁.而今识尽愁滋味,欲说还休.欲说还休,却道天凉好个秋 少年不识愁滋味,爱上层楼,爱上层楼,为赋新词强说愁；而今识尽愁滋味,欲断还休,欲断还休,却道天凉好个秋! 少年不识愁滋味,爱上层楼.爱上层楼,为赋新词强说愁. 　　而今识尽愁滋味,欲说还休.欲说还休,却道天凉好个秋! 少年不识愁滋味,爱上层楼.爱上层楼,为赋新词强说愁.而今识尽愁滋味,欲说还休.欲说还休,却道天凉好个秋. 少年不识愁滋味,爱上层楼.爱上层楼,为赋新词强说愁.而今识尽愁滋味,欲说还休.欲说还休,却道新 “少年不识愁滋味，爱上层楼。爱上层楼，为赋新词强说愁。而今识尽愁滋味，欲说还休。欲说还休，却道天凉好个秋！”对诗中描写的 《桑梓》作者是?少年不识愁滋味,爱上层楼,爱上层楼,为赋新词强说愁 　而今识尽愁滋味,欲说还休　欲说还休,却道天凉好个秋 少年不识愁滋味,为赋新词强说愁. "少年不识愁滋味,为赋新词强说愁.如今识尽愁滋味,却道天凉好个秋."的出处是那里呀 为什么“少年不识愁滋味,为赋新词强说愁”