Articles are among the last things learners master, partly because many Indian languages have no direct equivalent. Skipping them rarely blocks understanding, but it is one of the clearest markers of non-native English.

The one question to ask

Does my listener already know which one I mean?

  • If yes — use the.
  • If no, and it is one of many — use a or an.

"I bought a book." (you do not know which one yet)
"The book was excellent." (now you do — the one I just mentioned)

a or an?

It follows the sound, not the letter.

  • an hour — the h is silent, so it starts with a vowel sound
  • a university — sounds like "yoo", a consonant sound
  • an MBA — the letter M is said "em"

When to use no article at all

General plurals and uncountable ideas usually take nothing:

  • "Books are expensive." (books in general)
  • "I like music."
  • "She studies engineering."

Cases you simply memorise

Some uses have no logic worth chasing:

  • go to school, go to bed, go to work — no article
  • play the guitar, but play cricket
  • the Ganges, but Mount Everest
Do not let articles slow your speech. A missing "the" costs you almost nothing; a long pause costs you the listener.