picture_book, books

slippers, sandals, flip-flops, CL:雙|双[shuang1],隻|只[zhi1]

identical, the same

outer, surface, external, outwall, outside, exterior

shell, outward appearance, show, externality, visual aspect, exterior, effect, superficies, look, likeness, appearance, facade, surface, presentment, apparel, impression, facies, aspect, complexion, resemblance, semblance, guise, frontage, outwardness, rind, garb, showing, face, veneer, outside, garment, getup

pass/go through, be current or of general use