* Lives (as in plural of "life"): des vies
* Lives (as in verb "to live", present tense): vit (for singular) or vivent (for plural)
Here are some examples:
* They have many lives. (They have had many experiences.) -> Ils ont plusieurs vies.
* He lives in Paris. -> Il vit à Paris.
* The children live happily. -> Les enfants vivent heureux.
It's important to consider the context to choose the correct translation.