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second year of junior high school; second-year junior high school student
behaving in a way characteristic of teenagers going through puberty, esp. by being overly self-conscious; 2nd year of junior high sickness
息子は今年から中二になった。
My son became a second-year junior high schooler this year.
中二の時にバスケ部に入った。
I joined the basketball club in my second year of junior high.
中二は思春期のまっただ中で難しい時期だ。
Second year of junior high is a tough time right in the middle of puberty.