A glottal sound is a sound that is produced when the glottis is closed.

I am majoring in phonetics at university.

He is majoring in phonology at university.

The study of phonons is an important field in physics.

I am taking solfège lessons.

On is always maintaining a calm attitude.

He is hiding a secret.

That sound is very beautiful.

I like listening to music.

The benefits of this project will greatly affect the local economy.