Formal:
* N'est pas drôle: This is the most literal translation and is suitable for formal situations.
* N'est pas amusant: This means "is not amusing" and is also appropriate for formal contexts.
Informal:
* N'est pas marrant: This is a more casual way to say "is not funny."
* N'est pas drôle du tout: This means "is not funny at all" and adds emphasis to the statement.
* C'est pas drôle: This is a very informal way to say "it's not funny."
Examples:
* Formal: "Ce film n'est pas drôle." (This movie is not funny.)
* Informal: "Tes blagues ne sont pas marrantes." (Your jokes are not funny.)
* Informal: "C'est pas drôle de se moquer des gens." (It's not funny to make fun of people.)
It's also important to consider the tone you want to convey:
* Sarcastic: You could say "C'est tellement drôle" (That's so funny) with a sarcastic tone to express that you actually find it not funny.
* Critical: You could say "Ce n'est pas drôle, c'est plutôt déplacé" (It's not funny, it's actually inappropriate) to express that you find it offensive.
Ultimately, the best way to say "are not funny" in French depends on the specific situation and your desired level of formality.