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leading part; leading actor; leading actress
彼女は映画の主役に抜擢されました。
She was selected for the leading role in the movie.
今日のパーティーの主役は新郎です。
The star of today's party is the groom.
映画で主役を演じるのは今回が初めての経験です。
This is my first time playing the lead role.