The tongue movement is divided into four steps: ① The tip of the tongue presses the upper gum, licks the upper palate and hooks backwards. The deeper the hook, the better, but no.
Make the lingual frenum ache, then lick the palate with the tip of your tongue and slowly put it behind your teeth. (2) The tip of the tongue goes down, then slowly stretches out of the mouth and stretches out.
The longer the time, the better, and then take it quickly. ③ Push the left cheek with the tip of the tongue, so that the face bulges as much as possible, and then push the right cheek as well.
Cheeks, one left and one right, repeated many times. (4) the flat tongue gently bites the tongue surface with teeth, and the teeth stick out while biting the tongue.
Then bite it back slowly.
I hope it helps you.