on his/her/its
Il a beaucoup de livres sur son étagère.
He has a lot of books on his shelf.
Il prenait des notes non pas sur son UniBook, mais sur une liasse de papier.
He was taking notes not on his UniBook, but on a stack of paper.
Dès lors il vécut à plat ventre sur son parquet.
From then on, he lived face down on his hardwood floor.
Il a menti sur son expérience professionnelle.
He lied about his professional experience.
Ce gros con tente de doubler Maurizio sur son terrain.
This big jerk is trying to outmaneuver Maurizio on his own turf.
— Léon (1994)
Elle passa sa main sur son front, et resta quelques instants à réfléchir.
She ran her hand over her forehead and paused to think for a few moments.
Il faut mettre une pièce sur son front, et la faire tomber sans toucher le nez.
You have to put a coin on your forehead, and make it fall without touching your nose.
— La dolce vita (1960)
Hélas, le capitaine Jeffson était sur son bateau lorsque la tempête a éclaté.
Unfortunately, Captain Jeffson was on his boat when the storm broke.