Question

why did a e i o u is considered as vowels why not others

Answer 1

hlo mate.

here is your answer.

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A e i o u are considered as vowel because while pronouncing them they itself are pronounced without taking help from other letters whereas while pronouncing consonants we take help from the vowels.

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Answer 2

✍✍HERE IS YOUR ANSWER..⬇⬇
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$\underline{ANSWER}$➡

$\underline{\bold{WHAT \: IS\: VOWEL?}}$

A vowel is a type of sound. Vowel sounds are made only with the voice. A vowel is distinguished from a consonant by the lack of a significant obstruction impeding air-flow.A speech sound produced by vibration of the vocal cords but without any closure or narrowing of the speech tract such as would cause audible friction, capable of forming a syllable; a letter of the alphabet representing such a sound. 

$\underline{\bold{WHY \: A ,\: E, \: I ,\: O, \: U \: ARE }}$
$\underline{\bold{CONSIDERED\: AS \: VOWEL?}}$

In alphabet $\bold{A , E , I , O , U}$ have such characteristics while other alphabet from A to Z (Accept A , E , I , O , U ) have not. So only $\bold{A , E , I , O , U}$ are considered as $\bold{VOWEL}$.
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