The use of the article 'a' before a noun or adjective only when it starts with a consonant sound whereas the use of the article 'an' before a noun or adjective has a vowel sound.
<h3>What do you mean by a noun?</h3>
A noun represents any kind of living or non-living thing, place, action, etc. For example, humans, books, tables, chairs, etc. are considered nouns.
The consonant sound means the noun or adjective starts with the English alphabet apart from vowels. The vowel sound means the noun or adjective starts with the vowels like 'a, e, i, o, and u' respectively.
For example, if a noun like 'human being' starts from the consonant 'h' that means it should be written as 'a human being' whereas a noun like 'animal' starts from the vowel 'a' that means it should be written as 'an animal'.
Therefore, the use of an article depends on the sound of a noun or an adjective.
Learn more about the nouns in the related link;
brainly.com/question/134274
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