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medium (size); average (grade, level, etc.); middle
in; within; out of (e.g. ten people); among
during; while; in (the course of); within (a period); throughout
currently (doing); in the process of; in the middle of; under (e.g. construction, investigation)
middle way; moderation
second volume (of three)
junior high school; middle school
China
「中」 has other readings with different meanings.
このサイズは中でいい。
Medium size is fine for this.
十人中八人が賛成した。
Eight out of ten people agreed.
今、会議中なので出られない。
I'm in a meeting right now, so I can't leave.