1. Indefinite Articles: "a" and "an"

Use "a" before words that begin with a consonant sound. Use "an" before words that begin with a vowel sound.

A: I saw a cat.

An: She is an engineer.

• Use "a" before words starting with a consonant sound, even if the first letter is a vowel (e.g., a university).
• Use "an" before words starting with a vowel sound (e.g., an hour).

Omitting "a" or "an" due to incorrect understanding of sound rather than spelling (e.g., an university).

2. Definite Article: "the"

Use "the" before a noun when referring to something specific or already known to the reader/listener.

The: The cat is on the mat.

• Used before singular and plural nouns.
• Used in specific contexts (e.g., the sun, the president).

Omitting "the" when referring to specific entities or overusing "the" unnecessarily.

3. Zero Article

Used when referring to things in general or plural countable nouns without a specific article.

Dogs are loyal animals.

He enjoys playing the piano.

Misusing zero articles when specificity is required (e.g., using zero article when a specific context is intended).