When should I use "tu" and when should I use "vous"?

Unlike in English, there are two ways of saying "you" in French.Most of the time, when talking to someone, you will use "tu". This is normally used when talking to friends, family or people that you know well.There are two rules for using "vous" which are as follow:When you are talking to more than one person. For example: "Vous êtes une bonne équipe!", which means: "You are a good team!"When you are talking to someone that you want to address politely and show respect towards, often because they are older, in a position of importance, or maybe because you have never met them before. For example: "Bonjour Monsieur, comment allez-vous?", which means: "Hello Sir, how are you?"Note that, quite often, you may start by addressing someone using "vous", and then begin using "tu" as you get to know them better. If, however, you are not sure, just ask them. They will most likely be grateful that you did and it will make life a lot easier for both of you!