Using a character set repeated 1 or more times, make a pattern to search for strings that do not contain the characters 'a', 'e', 'i', 'o', 'u', and 'y'.
/[^aeiouy]+/gi
Next, surround our pattern with a word boundary on each side.
/[^aeiouy]+/gi
But wait, our pattern is considering strings containing white space to be misspelled words. Add the white space to the characters we wish to not match.
/[^aeiouys]+/gi
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