Question

use of indefinite articles a/an​

Answer 1

The indefinite article (a, an) is used before a noun that is general or when its identity is not known.

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Definite and Indefinite Articles (a, an, the)

COUNT NOUNS NON-COUNT NOUNS

Rule #1 Specific identity not known a, an (no article)

Rule #2 Specific identity known the the

Rule #3 All things or things in general (no article) (no article