我们的周年纪念日是六月十五日。

Our anniversary is on the ___fifteenth of June.

她把披萨切成十五份，我只吃了十五分之一。

She cut the pizza into fifteen pieces, and I only ate one ___fifteenth of it.

她的生日派对被安排在这个月的十五号。

Her birthday party is scheduled on the ___fifteenth of this month.