Savoir is another very useful but irregular verb. It is important to distinguish between savoir and connaître: savoir means to know a fact, or to know how to do something, whereas connaître means to know in the sense of being acquainted with a person or place. The other important point is that savoir is sometimes used when we would say in English that we can do something. ‘Je sais nager‘ means ‘I can swim’, i.e., ‘I know how to swim’. ‘Je peux nager‘ means ‘I can swim’ in the sense that I am physically able to, for instance because I had a broken leg and wasn’t able to swim for a time, but now I’m all right again.
Je sais – I know
Tu sais – you know (sing.fam.)
Il sait – he knows
Elle sait – she knows
Nous savons – we know
Vous savez – you know (pol.pl.)
Ils savent – they know (m.)
Elles savent – they know (f.)
(sing.fam.) – singular familiar
(pol.pl.) – polite plural
Perfect tense (passé composé)
J’ai su qui avait écrit la lettre. – I knew (found out) who had written the letter.
Tu as su faire les devoirs. – You knew how to do the homework.
Il a su de quoi il s’agissait. – He knew what it was about.
Nous avons su le faire rire. – We knew how to make him laugh.
Vous avez su comment faire une tarte aux pommes. – You knew how to make an apple pie.
Elles ont su faire du ski. – They were able to (knew how to) ski.
Je saurai les résultats demain. – I will know the results tomorrow.
Tu sauras conduire quand tu prendras des leçons. – You will know how to (be able to) drive when you take lessons.
Elle saura bientôt nager. – She will soon know how to (be able to) swim.
Nous saurons nous débrouiller. – We will know how to cope.
Vous saurez y aller à pied? – Will you know how to get there on foot?
Ils sauront la réponse la semaine prochaine. – They will know the answer next week.
sache – know (sing.fam.)
sachons – let’s know
sachez – know (pol.pl.)
sachant – knowing
Sachant la vérité, j’ai voulu lui parler. – Knowing the truth, I wanted to talk to him.
Il faut que je sache la vérité. – I must know the truth.
Il est content que tu saches conduire. – He is pleased that you can drive.
Je doute qu’il sache le poème par coeur. – I doubt that he knows the poem by heart.
J’ai peur que nous ne sachions pas retourner. – I’m afraid that we won’t know how to get back.
J’espère que vous sachiez nager. – I hope you can swim.
Il faut qu’elles sachent cuisiner. – They have to know how to cook.
With thanks to Elizabeth Allen