Raise the back of your tongue to touch the soft palate (velum). Stop the air, then release.

Americans pronounce cab as KAB (/kæb/). You'll hear it in sentences like "Harry managed to grab a cab back to the flat".
Record yourself saying "cab" and play it back. The mic stays on your device — nothing's uploaded.
1 syllable, 3 sounds. Explore each sound's mouth shape and how it's made.
Raise the back of your tongue to touch the soft palate (velum). Stop the air, then release.

Drop the jaw noticeably. Keep the body of the tongue low and forward, and don't let the back of the tongue raise toward the soft palate. Pull the lip corners back slightly, almost a starting smile.

Press your lips together, add vocal cord vibration, then release.
