Tongue twisters are phrases or sentences which are hard to speak fast, usually because of alliteration or a sequence of words with very similar sounds. Tongue twisters help develop speech skills in young children as well as older children who need additional help with speech therapy.
To get the full effect of tongue twisters you should repeat them several times, as quickly as possible, without stumbling or mispronouncing. Good luck!
Round the rugged rock, the ragged rascal ran.