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inside; interior
among; within
middle; center; centre
during; while; middle; midst; amid
interval; gap
mean; average
second (of three, e.g. sons, volumes); middle
medium grade; medium quality
「中」 has other readings with different meanings.
箱の中を見てみよう。
Let's look inside the box.
友達の中で彼が優しい。
Among my friends, he's the kind one.
かばんの中に財布が入っている。
There's a wallet inside the bag.