Hello there. Well, in my case, 2 years ago, I just took a wise decision before applying to a job: preparing the right French words with a teacher. I chose a private lesson in the school http://www.lutece-langue.com
, they were near Chatelet, and I studied a few weeks just what I needed for my field. The teacher was very kind and patient (!!) and in the end I was not only better prepared for the battle, but also more confident in me. Well, good luck!