When we are sinking into marshy ground while advancing and retreating must both be through quagmires - this is a terrain that will labor the cavalry.

• 汗下沮泽，进退渐洳，此骑 之患地也；左有深沟，右有坑阜，高下如平地，进退诱敌，此骑之陷地也。此九者，骑之死地也。明将之所以远避，暗将之所以陷败也。