When to Use a or An

A and an are two different forms of the same word: the indefinite article a that is used before noun phrases. Use a when the noun or adjective that comes next begins with a consonant sound. Use an when the noun or adjective that comes next begins with a vowel sound.

In which sentence we use an?

Names of StreetsNames of Oceans, Rivers, Seas, Deserts, Forests, CanalsUse a/an for non-specific an ocean a river a sea a desertUse “the” the Pacific Ocean the Mediterranean Sea the Potomac River the C & O Canal the Atlantic Ocean the Painted DesertNames of LakesNon-specific a lake

How do you use Aeiou?

The Rule. The rule states that “a” should be used before words that begin with consonants (e.g., b, c ,d) while “an” should be used before words that begin with vowels (e.g., a,e,i). Notice, however, that the usage is determined by the pronunciation and not by the spelling, as many people wrongly assume.