词汇	background subtration
释义	background subtration 背景减法
随便看	plan of seeking food plan of seeking road plan of sewerage system plan of site plan of small towns plan of stepping into hole plan of streets plan of study plan of study in nanjing university plan of subject construction plan of subsidence area plan of supply plan of talks plan of technical indices for freight traffic plan of the course plan of the course plan plan of the day plan of the living area plan of the number of staffs and workers plan of the overburden plan of the route plan of transposition plan of underground space plan of utilizing the minor products plan of wage fund