What types of phrases and clauses are set apart from the rest of the sentence using commas?

The correct answer is that nonrestrictive phrases and clauses are set apart from the rest of the sentence using commas. Nonrestrictive elements provide additional, non-essential information that can be omitted without altering the fundamental meaning of the sentence. For example, in the sentence "My brother, who lives in New York, is visiting this weekend," the clause "who lives in New York" is nonrestrictive; it adds information about "my brother" but is not necessary to understand who is being referred to. The commas indicate that this information is supplementary.

In contrast, restrictive phrases and clauses are essential to the meaning of the sentence and are not set off by commas. A restrictive clause, such as "the book that you lent me," specifies exactly which book is being talked about. If we removed the clause, the listener would not know which book is in question, hence no commas are used.

Descriptive phrases might provide qualities or characteristics about a noun, but they may or may not require commas depending on whether they are restrictive or nonrestrictive. Incidental phrases are not a standard grammatical category like restrictive and nonrestrictive, leading to potential confusion regarding their definitions. Understanding the distinctions helps in correctly punctuating sentences, ensuring clarity and precision in writing