这个成语出自《水浒传》第111回:“如今听得朝廷起大军来,与方腊厮杀,我这里正是风门水口。”它的意思是要冲、关键地点。巧合的是,在中越边境有一个水口河,越南称平江河,从越南流入广西,是两国的界河。水口河上有一座当年我国为支援越南抗击美国而修建的钢筋混凝 This idiom comes from the “Outlaws of the Marsh” 111th: “Now I heard the army from the court to fight, and Fangla fight, I am here is the throttle.” “It means to red, key locations.” Coincidentally, there is a Shuikou River on the border between China and Vietnam, while Pingjiang River is Vietnam’s capital. It flows into Guangxi from Vietnam and is a boundary river between the two countries. There is a river in the mouth of a river that China built to support Vietnam’s fight against the United States