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13th day of the month
13 days
十三日に届いた招待状を確認した。
I checked the invitation that arrived on the 13th.
来月の十三日に引っ越しを予定している。
I'm planning to move on the 13th of next month.
十三日が面接の日だと手帳に書いてあった。
It was written in my planner that the 13th was the interview day.