Explanation: A little mud mud pill, less metaphor; closure blocked. Described as difficult terrain, as long as a small amount of troops can guard. Usage: The main predicate; as attribute; describe the difficult terrain Source: "Han Wei Xiao Chuan" Yuan asked a pill for the big mud Wang Feng Hangu Pass. " Examples: Still willing to ~ and then closed for a Thousand Years, the rainy weather took a new good, long time is to look at flowers. ★ clear s "The Cherry Song" poem