Explanation: Beam horse: the horseshoe wrapped to prevent the horse slipping; hanging car: the car hook firmly, to prevent shedding. To wrap himself away, hanging up the hill to the car. Describe the dangerous situation along hilly. Usage: Joint type; as the predicate attribute; describe the dangerous mountain roads Source: Qin Guan "Fengshan pipe": "Beam horse hanging car, on the base of the mountain of the ear."