「中」(naka) means "inside," "middle," or "center." It refers to a position contained within something. For example, if you put something inside a box, you'd say, "箱の中に" (hako no naka ni), meaning "inside the box."

「中」(なか)は「内部」や「真ん中」という意味です。物の内部を示します。例：「箱の中。」