A few intoductory phrases & responses:
Est-ce que vous connaissez mon ami? (ess keh voo kahn ay say mohn ah mee) -Do you know my friend?
Non, je ne le pense pas (noh zhuh neh leh pahnce pah) -I don't think so.
Oui, nous nous sommes déjà rencontrés (wee noo noo some pah day zhah rahn kahn tray) -Yes, we've already met.
Oui, j'ai déjà fait sa connaissance (wee zhay day zhah fay sah kahn ay sahnce) - Yes, I've already met him/her
Instead of mon ami, you can substitute father, mother, sister, brother, etc.
Just remember, with males you would use mon, with females you would use ma, and with multiple people you would use mes whether they are male or female.
