\"The Sixth sick sheik\'s sixth sheep\'s sick\" has the Guiness World Record for toughest tongue twister.

Here\'s some more tongue-twisters (careful, these are tough): \"Can you can a canned can into an uncanned can like a canner can can a canned can into an uncanned can?\"

\"The seething sea ceaseth and thus the seething sea sufficeth us.\"

\"Imagine an imaginary menagerie manager managing an imaginary menagerie.\"

The sign language version of a tongue twister is a \"finger fumbler\". \"Good blood bad blood\" is supposed to be a hard sentence to sign and say, making it a tongue-twister and a finger-fumbler.

Here\'s some awesome tongue twisters, courtesy of Dr. Seuss:
Dr Seuss - Fox in Socks (Animated Book)
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