sentences:  For example, the front walls of the houses are horizontally placed white rectangles with simple black and gray lines to depict the edges and rooftop of each building.Doorways were painted in the same minimalistic manner, yet the contrast between the darkness inside the building with the lighter door frame is prominent enough to create a sense of depth.Wu’s attention to perspective and depth in Twin Swallow is a factor that distinguishes himself from many other traditional guohua painters.