Complex sentence: The other communities are in Valenzuela, where the Isleños speak French, and in Galveztown, where there are two Isleño communities that speak Nahuatl dialects, due to the influence of the dominant languages in those locales.
Split into simpler sentences: The other communities are in Valenzuela, where the Isleños speak French, and in Galveztown, where there are two Isleño communities that speak Nahuatl dialects. This circumstance is due to the influence of the dominant languages in those locales.