阅读下面这首诗,回答问题玉阶怨 (李白)玉阶生白露,夜久侵罗袜。却下水晶帘,玲珑望秋月。本诗诗题为《玉阶怨》,写宫女之怨,而全诗不着一“怨”字,作者是如何写出宫女之怨的?__________________________________________________________________________________________________________________________________________________________