A sequence of words or sounds, typically of an alliterative kind, that is difficult to pronounce quickly and correctly are called Tongue Twisters.
Practice these easy Tongue Twister at least five times each:
1.Stupid superstition!
2.Rudder valve reversals
3. Sheena leads, Sheila needs.
4. How can a clam cram in a clean cream can?
5. If Stu chews shoes, should Stu choose the shoes he chews?