An article is a word used with a noun. The commonly used articles are a, an, and the. A/an are called indefinite articles because the noun to which they refer is general (indefinite) and not specific. The is called a definite article because it refers to a specific (definite) noun.
The article 'a' is used when nouns start with a consonant.
I ate a watermelon for lunch.
In this sentence, 'a' (article) is used with watermelon (noun). The article is indefinite because it is not referring to a specific watermelon.
'An' is used with nouns beginning with vowels.
I ate an orange for lunch.
Here, 'an' (article) is used instead of a because orange (noun) begins with a vowel. Again, the article is indefinite because it is not referring to a specific watermelon.
The article 'The' is used when referring to a particular noun (person, place, or thing).
I ate the peach for lunch.
Here, 'the' (article) refers to peach (noun). The article is definite because it is referring to a specific peach; I didn’t eat just any peach for lunch, but the peach.
'A' is also used when a word begins with a vowel but sounds like it begins with a consonant.
She is a European.
Here, European (noun) is a noun beginning with a vowel, but it sounds like it begins with a Y and not an E. Thus a is used and not an.
'An' is also used when a word begins with a consonant but sounds like it begins with a vowel.
It is such an honor to meet you.
In this sentence, 'an' (article) is used to refer to honor (noun). Even though honor begins with h, it sounds like it begins with o, and thus 'an' is used instead of 'a'.
