A nonessential adjective clause should be set off with commas, but an essential adjective clause should be set off with semicolons.

Question

Quizplus · Accepted Answer

An essential adjective clause is not set off with commas or semicolons because it provides information critical to the meaning of the sentence, while a nonessential adjective clause should be set off with commas as it adds extra information that can be omitted without changing the fundamental meaning of the sentence. Semicolons are not used to set off adjective clauses.

A Nonessential Adjective Clause Should Be Set Off with Commas