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seventeen; 17
十七歳の夏に初めてアルバイトをした。
I had my first part-time job in the summer when I was seventeen.
参加者は十七名でちょうどよい人数だった。
There were seventeen participants, just the right number.
十七日間の旅は人生で最高の思い出だ。
The seventeen-day trip is the best memory of my life.