天险
天险 (tiānxiǎn) 天然地势险峻的所在 natural barrier
龙门
龙门 (lóngmén) 楚国都城郢城(现在在湖北省江陵县西北)的东门 the east city gate of the capital of Chu State in Warring States Period of 475-221 B.C.
清客
清客 (qīngkè) 旧社会在显贵人家或官僚地主家里帮闲的门客 proteges of the powerful who stay with their benefactions like parasites 豪门清客
陆游名句，再过龙洞阁名句。注释由系统生成，仅供参考
