Indefinite Articles
Indefinite articles are small words that signal a, an, or some and they help listeners know whether you mean any one thing or more than one. This guide focuses on the basic forms and uses in English.
Form
The indefinite article in English is a before consonant sounds and an before vowel sounds; some is used for plurals and uncountables. This small distinction helps speech flow smoothly and signals whether you mean one or more.
Usage
Use a or an to mention something for the first time or to refer to any single item of a type; use some for plural or uncountable amounts when you mean an unspecified quantity. Indefinite articles set up information that can become definite later.
Examples
A and An
Some
Summary
Indefinite articles signal an unspecific single item a*/*an or an unspecific quantity some, and they shape how listeners track new versus known information.
Suggested Reading
English File by Unknown (Oxford University Press series)
Practical English Usage by Michael Swan
English Grammar in Use by Raymond Murphy
English Grammar Workbook: Simple Grammar for Non-Native Speakers by SIMPLE English Language School
Essential Grammar in Use by Raymond Murphy
New Concept English by L. G. Alexander
Oxford Practice Grammar by Norman Coe, Mark Harrison & Ken Paterson
The Blue Book of Grammar and Punctuation by Jane Straus
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