all words have vowels in them
cauliflower
facetious
authoreiaetian
autau
"EAU" is the only all-vowel three letter word.
All words in the English language must have vowels. Even one letter words like 'a' or 'I'.
Unproprietary, miscellaneous
That is a trick question. You can't make a four letter word using all five vowels.
There are no common English words consisting of all vowels. Although A,E, I, O, and U are always vowels, Y and W can be used as vowels (e.g. Welsh). However, there are no instances where they are used as vowels along with only other vowels.Sequoia is a word using all of the vowels but not consisting of only vowels.
Without vowels, you can't pronounce the words. Try to pronounce frnc. It is furnace or franc without the vowels.
I is a word in English with only vowels.