《幼学琼林·卷三·宫室》
一定要学习宋代寇准抗击契丹进犯，才算得是北门锁钥。南朝檀道济文武全才，不愧是万里长城，南朝除了他，还有谁能抵抗北兵的。
宋寇准真是北门锁钥，檀道济不愧万里长城。
It is necessary to learn about Kou Zhun's resistance to the invasion of Khitan in the Song Dynasty, which is considered to be the key to the north gate. Tan Daoji of the Southern Dynasties is a versatile talent, worthy of being the Great Wall. Besides him, who else can resist the northern soldiers in the Southern Dynasties?