Would you please proofread a part of my essay?

Bilingual is who can speak two languages. There are people of bilinguals and monolinguals. I think that bilinguals can have more merits than monolinguals.
Monolinguals can only one language, therefore they cannot talk to people who speak the other language. However, we have a greater opportunity to talk to foreign at school, business, and so on. On the other side, bilinguals can talk to more people than monolinguals. Therefore, bilinguals can work well at business, or communicate with foreign friends at school.

Are these sentences natural?