Aug 16 2008
That or Which?
I wish I had a nickel for every time I’ve heard or read “that” when it should have been “which” or vice versa. The that/which issue is one of the most abused in the English language. I’ll be the first to admit that I’ve been among the frequent offenders and I’m sure I still get careless and blow it occasionally.
Before we look at the rule, let’s take a quiz. Are the following sentences correct or incorrect in terms of their use of “that” and “which”?
- The car which I want to buy is too expensive for me.
- The car, that won the Best Auto of the Year Award, is too expensive for me.
The answer? They’re both wrong. In the first sentence, “which” should be “that.” In the second sentence, “that” should be “which.” Here’s why:
RULE: “Which” is always used to introduce nonessential clauses. “That” is ordinarily used to introduce essential clauses.
Do you know the difference between essential and nonessential clauses? For that matter, do you know what a clause is? I could tell you that a clause is a group of words consisting of a subject and a predicate, but I won’t. Because if I did, I’d have to technically define what a predicate is (“a word or combination of words, including the verb, objects, or phrases governed by the verb that make up one of the two main parts of a sentence”) and by the time we covered that barren territory we’d only want to slit our wrists.
So let’s do it this way: A clause is a piece of a sentence that provides additional information about a word or phrase in that sentence. A nonessential clause can be pulled out of a sentence without changing the meaning of the rest of the sentence. If you pull an essential clause out of a sentence, it changes the sentence’s meaning.
So in sentence #1 the clause is “which I want to buy.” It’s an essential phrase because it identifies the car that is too expensive for me. Since it’s an essential phrase, it should be introduced with “that” rather than “which.” The clause in sentence #2 is “that won the Best Auto of the Year Award.” It is a nonessential clause because it is extra information that wouldn’t change the sentence’s meaning if it were deleted. So it should be introduced with “which” and not “that.”
I could go on and on about this, mentioning that (1) “who” should replace “that” and “which” when referring to people; (2) it’s often better to avoid repetition by using “which” instead of “that” if “that” has already been used in the sentence; (3) “which” is preferable to “that” when the sentence contains two or more parallel clauses; (4) essential and nonessential clauses are sometimes called restrictive and nonrestrictive clauses; (5) you should set nonessential clauses apart with commas, but usually not essential clauses; and (6) a lot of writers get sloppy on this because they want to get on with their lives.
Can you blame them?
I have been instinctively using the correct way without knowing the logic for it. The logic was an English teacher with a cane! Thanks for this clarification. Perhaps now I shall not make even the odd inadvertent mistake.
Unless you’re British, in which case you use “which” or “that” pretty much interchangeably.
I’ve often wondered exactly how this rule came about. When I read “literature” (as opposed to regular “low-brow” fiction), I am often struck that the writers we admire as classical authors frequently do not follow the “that” vs. “which” rule.
When I worked as a copy editor, we were draconian in our enforcement of “that” vs. “which.”