The Editor’s Manual
Free learning resource on English grammar, punctuation, usage, and style.
Use “that” as a relative pronoun in restrictive or defining clauses, which present information essential to meaning. Don’t use a comma before “that.”
Use “both” to refer to two people or things. “Both” and “both of” can sometimes be used interchangeably, but not always. Use parallel structure with “both–and.” No commas are needed around “both.”
“That” introduces information that is essential to meaning and not enclosed in commas. “Which” introduces additional, optional details enclosed in commas. In British usage, it also introduces essential information.
Both “than I” and “than me” are grammatically correct, since “than” can be used as either a preposition or a conjunction. “Than I” is seen more often in formal usage.
“It’s me” and “This is him/her” are generally acceptable in everyday usage. The strictly correct alternatives, “It is I” and “This is he/she,” are confined to highly formal usage.
“I” is a subject pronoun, while “me” is an object pronoun. In formal styles, use “I” in a compound subject and “me” in a compound object. “Me” is generally preferred in comparisons and after the “be” verb.
Pronouns starting with “some” and “any” indicate unspecified things and persons but convey different meanings and points of view in questions, statements, and conditionals.
“Some” and “any” both indicate quantity and are used in questions, statements, and conditionals, where they convey different points of view, assumptions, and expectations.
Use “you and I” as the subject and “you and me” as the object in a sentence. Avoid hypercorrection. “You and me” is used more often after the “be” verb and in comparisons.
“It’s” (with the apostrophe) is a contraction of “it is” or “it has.” “Its” (without the apostrophe) is the possessive form of “it.”