As writers, we’re often called upon to describe people, places, and things. I’ve written before about noun phrase appositives, which are handy little structures, but they aren’t the only tool for the job.
If you’ve got a passing familiarity with the parts of speech in English — thanks to the education you received in your formative years or, more likely, experience playing the game Mad Libs — you should be familiar with adjectives as “descriptive words.” For example:
Barbie drove her pink Corvette to Ken’s house, speeding the entire way: this was an urgent fashion emergency.
Adjective clauses, which modify nouns or noun phrases, are clauses which function adjectivally. You no doubt see them and use them all the time. Adjective clauses most commonly begin with who, whom, which, that, whose, where, and when. Below are some examples — the adjective clauses are in bold.
There’s the jerk who rear-ended my car.
Anthropologists discovered that Neanderthals, who were thought to be a separate species, were actually closely related to modern humans
It’s very disappointing to visit a donut shop which has just run out of donuts.
The Golden Gate Bridge, which spans the entrance to the San Francisco Bay, is one of the most iconic symbols of California.
Is this the new camera that you were talking about buying?
We fired the guy in tech support whose advice was always to “hit it with a stick,” or “hit it with a bigger stick” after the latest incident left our server room in ruins.
The city where my favorite movie was shot happens to be just down the coast.
I went to elementary school in the olden days, when computers used floppy disks and the only mobile phone any of us had ever seen belonged to Zach Morris on Saved By The Bell.
Using Commas with Adjective Clauses
You may have noticed that some adjective clauses are set off with clauses, and some are not. Setting the adjective clause off with commas can change the intended meaning.
For example, look a how the commas change the meaning in the sentence below:
The cake which was covered in chocolate frosting was eaten very quickly.
The cake, which was covered in chocolate frosting, was eaten very quickly.
In the first sentence, the adjective clause, “which was covered in chocolate frosting,” tells us which cake was eaten very quickly. The implication is that there were other cakes around, with other kinds of frosting. Maybe no one was really into the basic white buttercream slathered mile-high all over the store-bought sheet cake.
In the second sentence, the adjective clause “which was covered in chocolate frosting” is set off with commas. We already know which cake — the adjective clause just tells us more about it. And thanks to the adjective clause, we can get the sense that the chocolate frosting might be why it was so popular.
In this way, commas can also help us understand whether the adjective clause is describing all members of a group, or only some. For example, compare these two sentences:
School principals who enjoy their work tend to live longer than people in most other professions.
School principals, who enjoy their work, tend to live longer than people in most other professions.
When there’s no comma, the sentence is telling us that only those school principals who enjoy their work live longer. When the adjective clause is set off with a comma, the sentence is describing school principals as a class – saying that they all enjoy their work. That’s…optimistic.
So, when deciding whether or not you need to set off your clause with commas, feel free to consult the handy flowchart:
More formally, the kind of adjective clause that’s identifying “which one” is called a “restrictive clause, and the kind that simply describes the noun is called a “non-restrictive” clause — though you don’t have to know that to use them effectively. Feel free to call them “Princess Sparklepants clauses” and “Stinkypants clauses” for all I care. As long as you’re using your commas correctly, your meaning will be clear.
Which vs That
Although you’ll find plenty of advice online about a “rule” for using “which” vs “that,” I think the word “rule” is misapplied. Making careful choices about using “which” versus “that” is, in theory, another way (in addition to careful comma usage) to make meaning less ambiguous when you’re trying to differentiate between adjective clauses that are identifying “which one” of a noun you’re talking about, versus adjective clauses that are providing additional description about a noun. But this seems to be primarily a distinction made in American English, and even then, it’s a distinction made only by a subset of speakers and writers.
That said, the subset of speakers and writers who do adhere to this rule is likely to include teachers and editors, so, if you’re writing for an audience that expects you to differentiate, here you go: “which” should be used when the adjective clause is giving background information — when the adjective clause is non-restrictive, and set off with commas. In contrast, “that” should be used when the adjective clause is identifying “which one” — when it’s not set off with commas.
Commonplace “rules” of grammar, which are often not the actual rules of English syntax, are hotly debated.
The “rules” of grammar that are common knowledge are often not really “grammar rules” but notions about usage and style that subtly police social and cultural boundaries.
Personally, I tend to follow this “rule” when I think it makes my writing sound better and makes my meaning clearer, and decline to follow it if that makes my writing sound better/my meaning clearer, so you’ll see me using “which” in restrictive clauses when I think it the sentence reads better that way.
The following sentences include adjective clauses, which are underlined. In each sentence, decide if the adjective clause should be set off with commas or not. Add commas to those sentences which you feel need them.
- The great novelist Joseph Conrad who is probably best remembered for Heart of Darkness did not learn to speak or write English until he was 22 years old.
- We’re going to visit a wizard who has promised to send me back to Kansas.
- This coffee which is sustainably harvested by farmers who are paid a fair wage is expensive, but worth the price.
- I am boycotting all products that are produced using child labor.
- Varney’s favorite TV show is Community which is a comedy set at a community college.
Combine the following sentence pairs. Turn the second sentence in each pair into an adjective clause.
- I’m going to buy those cute boots. They are on sale right now.
- Oren called on a student in the back row. She had hesitated before raising her hand.
- The manufacturing plant was closed due to safety concerns. It had been cited numerous times by various federal agencies.
- Edna recently visited her dentist to have a tooth pulled. Edna suffers from frequent toothaches. Her dentist has an office decorated with antique dental equipment. Having her tooth pulled caused her cheek to swell up like a balloon.
- An architect recently designed a new type of bridge. It is earthquake-proof.
Answers to Exercise 1:
- Set off with commas
- No commas
- No commas
- No commas
- Set off with comma
Answers to Exercise 2:
- I’m going to buy those cute boots, which are on sale right now. Also correct: I’m going to buy those cute boots that are on sale right now.
- Oren called on a student in the back row who had hesitated before raising her hand. Also correct: Oren called on a student in the back row, who had hesitated before raising her hand.
- The manufacturing plant, which had been cited numerous times by various federal agencies, was closed due to safety concerns.
- Edna, who suffers from frequent toothaches, recently visited her dentist, who has an office decorated with antique dental equipment, to have a tooth pulled, which caused her cheek to swell up like a balloon.
- An architect recently designed a new type of bridge that is earthquake-proof.