1. Is used to indicate an individual or element of any kind, species or gender without particularizing it when we introduce it in a sentence or a discourse.
1.1. There are two diferent forms of singular indefinite articles: "a" & "an"
1.1.1. Rules to use "a"
1.1.1.1. Use "a" when the noun that accompanies the article begins with a consonant (or a vowel with a consonant sound) Examples: - a car - a doctor - a table - a horse
1.1.1.2. Use "a" with singular nouns after the words 'what' and 'such' Examples: - What a shame! - She's such a pretty girl - What a lovely day!
1.1.2. Rules to use "an"
1.1.2.1. Use "an" when you have to introduce words that start with a vowel sound. Examples: - an orange - an umbrella - an apple - an elephanlt
2. In English, the indefinite article "a/an" is only used ON SINGULAR
2.1. For example
2.1.1. You have a rabbit (singular) You have some rabbits (plural) You have many rabbits (plural)
2.1.2. I have an apple (singular) I have some apples I have many apples
3. There are some exceptions to apply the indefinite articles
3.1. Exceptions to apply "an"
3.1.1. If you are using a word with a silent "h", then you have to use "an"
3.1.1.1. Honorable Right: Joshua is an honorable man Wrong: Joshua is a honorable man
3.2. Exceptions to apply "a"
3.2.1. When the "u" or "eu" has the same sound as "you" you must use "a"
3.2.1.1. Unicorn Right: I want to be a unicorn Wrong: I want to be an unicorn European Right: We had a european trip Wrong: We had an european trip
4. Comparing right and wrong uses of "a" & "an"
4.1. Right
4.1.1. an hour
4.1.2. an apple
4.1.3. an honor
4.1.4. an engineer
4.2. Wrong
4.2.1. a hour
4.2.2. a apple
4.2.3. a honor
4.2.4. a engineer