“碧云天,黄花地;西风紧,北雁南飞。晓来谁染霜林醉,总是离人泪。”《西厢记》中,崔莺莺这样唱道。作者王实甫以“北雁南飞”的点睛之笔,刻画出崔莺莺思念亲人的离愁别绪。雁是一种大型游禽,大小、外形一般似家鹅,或者比家鹅稍小些。雌雄羽色相似,多数种类以淡灰褐色为 “Biyun days, yellow flowers; tight westerly, North Yan South fly. Xiao who dyed frost Lin, always tear.” “The West Chamber”, Cui Yingying sang this way. The author Wang Shi-fu to “North goose Nanfei ” the crowning touch, portrayed Cui Yingying miss their loved ones do not worry. Goose is a large poultry, size, appearance is generally like a goose, or slightly smaller than the goose. Female and feather color similar to most species to light gray brown