you know how to do
Je dois savoir ce que tu sais faire.
I need to know what you can do.
Tu sais faire couvrir la patinoire gratis au Chicago Stadium ?
Do you know how to get the ice rink covered for free at Chicago Stadium?
— Presque Célèbre (2000)
How do you know how to do that?
Et toi, qu'est-ce que tu sais faire ?
And you, what can you do?
Do you know how to do that?