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junior high school student; middle school pupil
中学生のとき、毎日部活に通った。
When I was a junior high school student, I went to club activities every day.
この本は中学生にも読みやすい。
This book is easy to read even for junior high school students.
近所の中学生が自転車で通学している。
Junior high school students in the neighborhood commute by bicycle.