I proposed that this basic muscle kit is sufficient to navigate round vowels and diphthongs, and most of the consonants. The point about these 4 buttons is to learn to move each at will. They already operate as part of the habit of the learner’s mother tongue, but to learn the new moves of the new sounds of a new language learners need to move these muscles free of the grip of the mother tongue habit. That is, from choice. So part of what follows consists of turning a habit into a choice.