can I use voiceover to read french text ?
Yes and no. It will read it but the accent and phrasing probably won;t be very good.
The thing to do is to try it yourself and see if it meets your needs.
When I had OS 10.6, I couldn't read foreign languages.
The Mountain Lion 10.8 has foreign voices already installed.
I'm sorry I don't have the asnwer for Lion 10.7.
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