Two sounds close enough to trade places: the “th” of think and the “ch” of chair. Swap one for the other and a different word comes out — this page is how to keep them apart, in both directions.
Do not press the tongue to the ridge and release; hold the tongue tip between the teeth and blow smoothly with no burst.
“You explode the sound like uncorking prosecco! No explosion, bello. Tongue between teeth, air flows calm like a Sunday.”Nunzio, when he hears it
You cannot hear your own swap. That is the whole problem.
Nunzio records you reading a sentence, scores every sound in it on your phone — nothing is uploaded — and tells you which of these two actually came out. Nunzio — Accent Coach is coming to the App Store and Google Play.