Articles in the English language are placed before nouns and never appear on their own. They can be either definite (the) or indefinite (‘a’ or ‘an’). The following rules should be kept in mind when using articles:

1. The definite article ‘the’ is used with countable or uncountable nouns, either in the singular or plural form:
   • “The house is huge.”
     • countable and singular
   • “The money was spent.”
     • uncountable
   • “The books are interesting.”
     • countable and plural
2. On the contrary, the indefinite article ‘a’ or ‘an’ is employed predominantly with countable singular nouns. The difference between both words is:
   • ‘a’ is employed whenever the noun begins with a consonant or when the first letter is pronounced as a consonant:
     • a book
     • a girl
     • a unit
       • Note: Although the letter ‘u’ is a vowel, it is vocalised like a consonant with the pronunciation [ju] in this case.
   • ‘an’ is used when the following word starts with a vowel or a letter that is pronounced like a vowel:
     • an office
     • an apple
     • an hour
       • Note: Same particularity as above. Although the letter ‘h’ is a consonant, it is spoken like a vowel here, which means the ‘h’ is not pronounced.

The following explanations relate to the topic ‘Definite and indefinite articles (a, an, the)’ and might also be interesting for you:

• Countable nouns in English
• Uncountable nouns in English
• Exercise 1: English articles ‘a, an, the’