Olfactory cells play an important role in allowing us to sense smells.

Olfactory cells play a role in sensing smells in the nose.

Every day, I use autosuggestion to boost my confidence.

He is so narcissistic that he doesn't listen to others' opinions at all.

His self-assertion is too strong, sometimes causing trouble for others.

Neurons are responsible for transmitting information in the brain.

Macrophages play a role in taking in and breaking down foreign substances in the body.

Oocytes play an important role in the reproduction of organisms.

I think his actions are just for self-satisfaction.

He is drawing pictures just for self-satisfaction.