The relative pronoun "that" is used with essential (restrictive) clauses, which provide crucial information needed to identify the noun they modify. For example, in "The book that I borrowed is fascinating," the clause specifies which book is being referred to. In contrast, "which" is used with nonessential (nonrestrictive) clauses, adding extra information that can be omitted without changing the sentence's meaning, as in "The book, which I borrowed from the library, is fascinating." In summary, use "that" for essential details and "which" for additional context.

Answer 1

Your explanation of the usage of "that" and "which" is clear and accurate. To summarize:

1. "That" is used for essential (restrictive) clauses, which are necessary to specify or limit the noun they modify. The information in these clauses is crucial for understanding the sentence. Example: "The car that I want is red." Here, "that I want" identifies which car is being referred to.

2. "Which" is used for nonessential (nonrestrictive) clauses, which provide additional information that can be removed without altering the overall meaning of the sentence. Example: "The car, which is parked outside, is red." The clause "which is parked outside" adds extra information but is not necessary to identify the car.

In essence, use "that" for information critical to the meaning and "which" for supplementary details.