Native french speaker here. I would have translate "don't speak English" into "ne parlent pas anglais" instead of "ne parlent pas un mot d'anglais", as "pas un mot" is kind of an emphasis which is not is the original text.

There is also a typo : "devant" -> "devenant"

Finally I wouldn't put a comma before "en français" at the end of the line. To me, the sentence makes more sense without it.

Good job though ! That was just my 2 cents :)