Try this at home (don't worry, it's not dangerous.) Arrange the letters on opposite ends of the Hebrew alphabet together: Aleph and Tav, Bet and Shin, Gimel and Resh, Dalet and Koof, Hei and Tsadi, and Vav and Pei.

The first letter of each couplet stands for the number of the day of Passover, and the second letter of the couplet stands for the initial of the holiday that falls on that day of the week.

Aleph:The first day of Pesah falls on the same day of the week as Tisha B'av, the 9th of Av.

Bet: The second day of Pesah falls on the same day of the week as Shavuot.

Gimel: The third day of Pesah falls on the same day of the week as Rosh HaShana.

Dalet: The fourth day of Pesah falls on the same day of the week as Kriat HaTorah (a reference to Simchat Torah, when the Torah cycle both concludes and begins.)

Hei: The fifth day of Pesah falls on the same day of the week as Tzom Kippur, the Fast of Yom Kippur

Vav: The sixth day of Pesah falls on the same day of the week as the previous Purim.