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The Indefinite and Definite Articles

The Indefinite Articles

The indefinite article is used to describe when the recipent doesn’t know which object is being referred to (generally singular)

For example

A
A box,   referring to a box, but not a specific box.
A pie,   any old pie, a Christmas tree, a cassette player.
An
An orange,   referring to an orange, but which one ?
An elephant,   There's a herd of 'em, an apron, an intellectual

Which brings us to when to use “a” or “an”. Generally “a” is used when the object starts with a consonant or it begins with a “you” sound, but this is not always the case.

For example
A chicken,   begins with a consonant.
A lorry,   because it begins with a consonant. but
An articulated lorry   the adjective describing which type of lorry starts with a vowel.
Hotel, is a great example, if you pronounce the h, you would generally say a hotel, but if you drop the h and prefer to say "otel" you would generally say an (h)otel,

a hotel.

an (h)otel.

a holiday,  as it starts with a consonant.

a university.  begins with a vowel but starts with a "you" sound.

a ukulele,   starts with a "you" sound, as above.

an uncle,  no "you" sound.

The Definite Article

The Definite article is used to describe when the recipent does know which object is being referred to (again, generally singular)

For example

The

the box,   referring to a box, yes, that one there.

The pie, the Christmas tree, the cassette player.