The ultimate most difficult tongue twister, as featured on BBC Radio 4 a few years back ~
Peggy Babcock
I heard the Betty Botter one before only different.
Betty Botter bought some butter but the butter betty botter bought was bitter butter, so betty botter bought some better butter, better than the bitter butter betty boter bought before.
Or something like that,
If you say Elephant over and over it sounds like telephone. Also works with Gullable some how.
Alligators are angry against alleycats and are acting absurbed among animals anxiously eating applejacks with amazement.
try that a few times and see if you don't get your self in a knot...
Can a cat caught in a can carry close connections while changing and contacting carnations and clovers.
Joan just jammed with a jack-o-lantern and a jelly roll which joggles, jiggles, and juggles the mind.
try that one a couple of times real fast..
Turkey tipped toe through time thirty times.
The sixth sheik's sixth sheep's sick.
Peggy Babcock
I remember my mother teaching me that in the fifties!.
Toyboat, as mentioned above is hard to beat for simplicity and impossibility.
Les chaussettes de la duchesse et de l'archiduchesse sont seches et archi-seches. (sorry no accents) certainly gives your environment a good salivation.
Black bees buzzing by butterflies bring brisk broad boxers bounded bundles busy burrows.
