Using “A” or “AN” Before a Noun in Research Articles

This podcast discusses when to use indefinite articles and which one to use. There are two indefinite articles in English: “a” and “an.” The word indefinite as related to grammar means something that has not been identified, is generic, or is an unfamiliar person or thing. You use an indefinite article when you are introducing new information, when the reader does not know exactly which noun you are referring to, or when the noun is not unique.

Always Singular and Always Plural Nouns

This podcast provides a handy short list of uncountable nouns (which are always singular) and a few countable nouns that are always plural that are commonly used in science and medical writing.