Articles are short words that may be found in almost every sentence. They include ‘a' and ‘an' (indefinite articles) and ‘the' (definite article). Articles are simple to use but wrong use of an article may cause a serious grammatical mistake.
1. Indefinite articles ‘a' and ‘an' are used before singular countable nouns.
The article ‘a' is used before a word beginning with a consonant sound while the article ‘an' is used before a word beginning with a vowel sound.
2. The definite article ‘the' is used before
i. Defined specific nouns.
iii. A noun that has been mentioned before.
Examples of 1
A liquid sample assumes the shape of its container.
An apple a day keeps the doctor away.
Examples of 2
i. The Pythagoras theorem relates the three sides of a right triangle.
ii. All matters have the tendency to possess the lowest possible energy.
iii. We were provided a liquid sample to test its properties. The liquid sample was found to be very viscous.