Map of the applications and rules for the articles A, AN
Rules for using "A / AN".
In the following sentences:
60 miles an hour = 60 millas por hora.
Two pounds a dozen = Dos libras la docena.
Fifty pesetas a kilo = A cincuenta pesetas el kilo.
What a pity! =¡Qué lástima!
What a fright! = ¡Qué susto!
Such a nice girl! = ¡Una chica tan simpática!
Half an hour = Media hora.
Half a dozen = Media docena.
Without a hat = Sin sombrero.
In front of "hundred", "thousand", "million":
a hundred pounds = cien libras.
a million pesetas = un millón de pesetas.
a thousand men = mil hombres.
Facing religions:
She is a Moslem = Ella es musulmana.
I am an Evangelist = Soy evangelista.
In front of the professions:
I am a teacher = Soy profesor/a.
He is an architect = El es arquitecto.
Faced with the nationality of the people used as names:
a German = un alemán.
an American = un americano.
When to use "an".
When the "u" has the same sound as the "y" in "you", or the "o" has the same sound as the "w" in "won", then you must use "a".
An example would be "a one-legged man" and "a European trip".
"An" is used when the word that follows begins with a vowel or "h" without sound.
an actor = un actor.
an engineer = un ingeniero.
an egg = un huevo.
an hour = una hora.
When to use "a".
Exceptions.
If you are using a word with 'h' without sound.
As 'honourable' or 'honest', then you must use 'an'.
Therefore, he would be "an honourable man" and "an honest mistake".
Use "a" in front of a word that starts with a consonant or "h" sucked.
Examples:
a boy = un chico.
a woman = una mujer.
a soldier = un soldado.
a house = una casa.
