密不通风

Explanation: Described the siege or defense tight close, the wind does not go through. 　　Usage: Supplemental; as the predicate attribute; analogy to work closely 　　Source: Yuan Ji Junxiang "Orphan" Second off: "But to visit the orphans have it anyway, certainly on the Tai Ping Zhuang Yong Bing Wei, drum-like airtight." 　　Examples: It turned out that the military had heard about the Institute for granted by the capture of Qin Fan, like they had Miyu Feng, Yuan Men led troops in the defense, ~. (Qing Xia's "flavor of" eighty-second back)