A s a French teacher, I hear my students making the same common mistake when expressing I know… Of course, it is quite confusing, as the French language has two verbs that can be translated into English by to know! Therefore, you have to choose between savoir or connaître; and you have 50% chance of getting it right. I hope I can help you understand how to decide which one to use through the following explanation and role plays:

Savoir and connaître are used in different contexts and can describe different aspects of knowing.

Let’s start with Savoir:
We use it mostly to express something that we know how to do.
For example, I know how to speak French = Je sais parler français.
Savoir is normally followed with another verb in the infinitive form.

Savez-vous faire du ski ?
Elle sait faire la cuisine.

We also use savoir to say that you know something, a fact: I know where Juliette is = Je sais où se trouve Juliette.
Je ne savais pas ça = I didn’t know that.
Nous savons ce que nous devons faire = We know what we should do.
Qu’est-ce vous en savez ? = What do you know about it?

Connaître:
It is mostly used to express that you know someone, something, a place…
Ex: I know France = Je connais la France.
I know geography = Je connais la géographie.
Do you know Alain? = Connais- tu Alain ?

Note: Usually when the verb connaître or savoir is used in a question, you can reply with the same verb.
E x a m ple: Est-ce que vous savez faire des crêpes? = Do you know how to make crêpes?
Oui, je sais! = Yes, I know how to!
Est-ce que vous connaissez le livre “Le Petit Prince”? = do you know the book “Le Petit Prince”?
Oui je le connais bien ! = Yes, I know it well!

Something that might help you to keep these 2 verbs straight: you will notice that most of the time savoir will be
followed by another verb in the sentence (the 2nd verb can be placed right after savoir or later in the sentence): Vous savez conduire un camion ? Whereas connaître is just followed by a noun: Tu ne connais pas Marie ?
More examples:
Je sais que vous ne pouvez pas venir aujourd’hui = I know that you cannot come today.
Je sais que votre femme ne mange pas de viande = I know that your wife doesn’t eat meat.
Je connais la situation. Ne vous inquiétez pas ! = I know the situation. Don’t worry!
Je connais votre idée. Venez me voir ! = I know your idea. Come and see me!