My birthday is on the thirty-first.

My father is thirty-five years old.

My father is thirty-eight years old.

It is thirty-seven kilometers to my house.

My family consists of thirty-six people.

This game uses three-dimensional graphics.

He is good at solving arithmetic problems.

Tritium is one of the radioactive isotopes.

The thirty-first day is my birthday.

He defeated the enemy using the Thirty-Six Stratagems.