General:
* Par-dessus: This is the most common and general translation. It literally means "over" or "on top of."
* Au-dessus de: This means "above" or "over." It is more formal than "par-dessus."
Specific contexts:
* Au sommet: This means "at the top" or "on top of." It is used for something that is located at the highest point.
* Sur le dessus: This means "on top of" and is used for something that is physically placed on top of something else.
* Par-dessus le marché: This idiom means "on top of that" or "in addition to that."
Examples:
* "Put the blanket over top of the baby." -> "Mettez la couverture par-dessus le bébé."
* "The bird flew over top of the house." -> "L'oiseau a volé au-dessus de la maison."
* "The mountains are over top of the town." -> "Les montagnes sont au sommet de la ville."
* "We got a free gift over top of the purchase." -> "On a eu un cadeau gratuit par-dessus le marché."
It's important to consider the context to choose the most appropriate translation.