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active duty; active service
student taking (university) entrance exams while still enrolled in school; student who passed their university entrance exams on the first try
現役の選手として試合に出場する。
He is participating in the match as an active player.
現役を引退する日が近づいている。
The day to retire from active duty is approaching.
彼は現役として活動を続けている。
He continues to work as an active member.