in the living room, the sofa background wall is hollowed out, which has the effect of expanding the space and making the living room look more spacious and bright. The hollowedout part can be used to place some decorations, such as green plants, books, or artwork, to add a touch of vitality and personality to the living room. The hollowedout part can also be used to create a sense of hierarchy and layering in the living room, making the space more interesting and dynamic.