must have
Il a dû se passer quelque chose.
Something must have happened.
Il a dû être plus malin que Vizzini.
He must have been smarter than Vizzini.
— Princess Bride (1987)
Il a dû mourir pendant la nuit.
He must have died during the night.
— Le Seigneur des anneaux : Les Deux Tours (2002)
Il a dû quitter la ville, alors il a déménagé à Berlin.
He had to leave the city, so he moved to Berlin.
Il a dû se conformer à sa décision.
He had to comply with his decision.
Il a dû avouer qu'il était responsable de l'erreur.
He had to admit that he was responsible for the mistake.