Grammar Tips

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Below is an excerpt from today's email:

That vs. Which

Last week’s grammar tip focused on the rules for using who vs. that. This week, we will learn the rules to guide us on when to use that vs. which.

Rule 1: That may refer to people, animals, groups, or things. (As mentioned last week, who is preferred when referring to people.)

Rule 2: Which refers to animals, groups, or things.

Since that and which may each refer to animals, groups, or things, how do we know when to use that and when to use which?

Rule 3: That introduces essential clauses while which introduces nonessential clauses.

Example: I do not trust editorials that claim racial differences in intelligence.

We would not know which editorials were being discussed without the that clause.

Example: The editorial claiming racial differences in intelligence, which appeared in the Sunday newspaper, upset me.

The editorial is already identified. Therefore, which begins a nonessential clause.

NOTE: Essential clauses do not have commas surrounding them while nonessential clauses are surrounded by commas.

Example: Chess is a game that requires intense concentration.

The second part of the sentence is essential for conveying the meaning of the sentence.

Rule 4: If this, that, these, or those has already introduced an essential clause, you may use which to introduce the next clause, whether it is essential or nonessential.

Example: Those responses to the questions, which were not well thought out, eliminated him from further job consideration.