directional, noun, place word, punctuation, verb, time word, particle, modal particle, numeral, adverb · the interior, internal part, or space within something

那个蓝色的书包里装满了他上课需要用的各种书本。

directional · the inner layer or surface of a garment, bag, or fabric

这件皮衣的面儿是黑的，里儿是红的。