A person who does not speak is called mute or nonverbal.
You call them 'mute'.
mute
quiet
A person who can speak two languages is called a bilingual.
If you want to call her do it when you feel comfortable but it is always best to speak in person.
If someone is unable to speak, it's called being 'dumb'.
no you dont
Hysterical.
A person who can speak different languages is called a polyglot.
Dial the person's phone number. When the phone is answered, start talking.
I think a tri-lingual person.