10th day of the month
ten days
１０日に届くはずだ。
It should arrive on the 10th.
レポートは１０日が締め切りだ。
The report is due on the 10th.
来月の１０日に友だちと温泉に行く約束をした。
I made plans to go to a hot spring with a friend on the 10th of next month.