Indefinite articles ( A, An )
A and An are indefinite articles used to refer to a singular countable noun.
The rule states ‘’ a ‘’ should be before words that begin with consonants (b, c, d ect).
Eg : * a car, * a hotel, * a university.
While ‘’ an ‘’ should be used before words that begin with vowels ( a,e,i,ect).
Eg : * an animal, an elevator, an hour/an honest man
it should be noted however, that the usage is determined by the pronunciation and not by the spelling, and this includes abbreviations and acronyms . to simplify one uses ‘’ a before a word that begins with a consonant sound and ‘’ an before a word that begins with a vowel sound .