Article

                An article is a word used to modify a noun, which is a person, place, object, or idea. Technically, an article is an adjective, which is any word that modifies a noun. Usually adjectives modify nouns through description, but articles are used instead to point out or refer to nouns.

The most important thing is to choose the right article in forming a sentence, and this is done by categorizing the noun as count and uncount. 

Count Noun - A count noun can have a number in front of it such as: 5 apples, 3 teachers, 10,00,000 people etc.

·        One must put an article in front of a singular count noun.

·        One can make a count noun plural and put a number in front of it.

·        One can put both a/an and the in front of a count noun.

·        One must use a plural count noun with no article if you mean all or any of that thing.

·        Use an (not a) when the next word (adverb, adjective, noun) starts with a vowel sound.

·        One must usually use a/an with a count noun the first time you say or write that noun.

Uncount Noun - An uncount noun cannot have a number in front of it One cannot put a number in front of an uncount noun and make it plural.

·        One cannot say a/an with an uncount noun.

·        Use an uncount noun with no article if that thing is meant in general.

·        Use the with an uncount noun when talking about a particular example of that thing.