It's important to believe in yourself.

He took a deep breath and calmed himself down.

His voice had the power to calm the entire room.

He took a deep breath in an attempt to calm down.

He took a deep breath to try to calm down.

He has confidence in his own abilities.

This park is known for its tranquility.

This lake is very tranquil, it calms the mind.

You should protect your own health.

He has the ability to change into a wolf.