Comment by lloeki

Don't worry it's no better on iOS, where I too have a English+French QWERTY setup, and where it too frequently decides to "helpfully" correct using an English dictionary several words into a unambiguously French sentence; or the other way around depending on wind direction and age of the captain.

Even more damning is that there seems to be three independent layers to the feature ("three suggestions" area above keyboard, autocorrect-as-you-type, correction popup as you touch a word) and neither agree with each other about which language it should be using.