translation of entry meta

Hello,
i just need to personnalise a few entry meta.
– traducing “posted on” in french
– put (and traduce )”author” instead of “leave a comment”

and also
– Traducing “posted in” in french
– Traducing”search…”
– Traducing “tagged”
Do i need to do it with poedit even if i just need to traduce 5 items on 279 or can i do it in the code? and how?

thank you.
http://www.oeilsurlacompublique.com/