Secondary valences play an important role in chemical reactions.

My second aunts are coming to visit me next week.

Secondary phosphines are commonly used in organic synthesis.

Secondary works are important for understanding the primary source.

The second normal forms are important in database normalization.

The second acts of the play were even more captivating than the first.

The second cosmic velocities of the planets in our solar system vary greatly.

The second officers are responsible for assisting the captain in navigating the ship.

Secondary victimisations can have a lasting impact on survivors of crime.

She is second-acting in the play.