Friday, July 4, 2008

Which vs. that

“Of all the gin joints in all the towns in all the world, she walks into mine.”
—Rick Blaine (Humphrey Bogart) from the 1942 movie, Casablanca

When Rick says this line in Casablanca, he is narrowing down, or restricting, his discussion from many possible gin joints down to the one he owns. In other words, of all the gin joints it could have been, she walked into that particular one. This concept of mentioning an item of which there are many, then adding more information
to narrow it down to the specific one you mean, is called “restricting the discussion.” From this concept comes the grammatical word for this: restrictive.
Why do we need to understand the concept of “restrictive”? Because it helps us know when to use “which” and when to use “that” when we are adding additional description to a sentence.

The words "that" and "which" are both used to add further description after a noun in a sentence. The word "that" is used when the additional information is needed in order to restrict the discussion down to the exact noun that is meant. "Which" is used to add extra information that is not really needed in order to identify the exact noun.

Let’s look at a specific example.

A. “The river is very muddy today.”
B. “The river that flows from Minnesota to Louisiana is very muddy today.”

As a reader of sentence A, you are probably wondering, “what river?” The noun “river” could mean any river in the world. You need more information to help you identify exactly what river I am talking about. When I add “that flows from Minnesota to Louisiana” in sentence B, you probably now realize exactly what river I mean: the Mississippi. The clause “that flows from Minnesota to Louisiana” narrows my discussion down, or restricts it, from all the possible rivers in all the world to the one I am talking about: the Mississippi. The word that is used to begin what is called a restrictive clause.

Here are two different examples:

C. The Atlantic Ocean separates England from the United States.
D. The Atlantic Ocean, which is sometimes called The Big Pond, separates England from the United States.

The word "which" adds information that is not needed to restrict the discussion. When I start sentence C with “The Atlantic Ocean,” I have already specified the exact ocean. You do not need any more information to help you identify exactly which gin joint—I mean ocean—I am referring to. In other words, no further restriction is needed to make my meaning clear. But I just felt like adding further description or information, so I added “which is sometimes called The Big Pond” in sentence D. I put this additional information inside two commas to indicate that it is not really necessary.

You can think of the two commas around a nonrestrictive clause as miniature parentheses, indicating that the clause is merely parenthetical. You could take out the part of the sentence between the commas, and the reader would still understand the sentence and not be left wondering what you were talking about.

Use this little chart as a reminder:

That is restrictive (and essential)and has no commas.
Which is nonrestrictive (and nonessential) and has commas.

10 comments:

Anton said...

Hello Jennie, thank you very much for the article, I find it very useful for me as a non-native speaker.
Would you possibly shed light on using the word which in questions?

Unknown said...

Can an advanced Sentences Grammar Checker transform our writing assignments correct and professional? How does it work? Writing proper English is now more important than ever since many of us increasingly communicate with others thanks to computers and the Internet. See more complex sentence checker

Unknown said...

You can extend your English conversation by choosing to talk about common topics that are common to the context.http://vietnamhairextensions.com/

Angel Claudia said...

Our Pay for custom written college papers services makes your college life bearable and also receive the best assignment writing service fulfilling by enabling you to pass your exams and also in other research and essay writing tasks.

Puremelda said...

In the quest for quality grades, students have realized the need for working with Nursing Paper Writing Service agencies that specialize in various types of essay writing. They are the best company that handles Best Proofreading Service and Affordable Editing Services.

meldaresearchusa said...

Whether the Custom Research Papers focuses on a single subject or compares two approaches, our Coursework Writing Service comes in with the Cheap Editing Services to complete the homework.

dorcassmith said...

To further enhance cost-effectiveness of Custom Research Paper Services, there is a revision policy for the Custom Research Paper Writing Services where essayist review the task, despite the period that has elapsed since we presented your Legitimate Custom Research Paper assignment.

Sam said...

My Assignment Help Australia has pioneered for its quality services, that has brought closer to our customers. We do not only wish to gather vast populace, but also aim to connect with them as their assignment help partners.

Masters Homeopathy said...

Masters Homeopathy Appreciate you Informative blog. It is really very helpful information.
Best homeopathy doctor near me
Homeopathy doctors near me
Best Homeoapthy Doctos in Hyderabad
Homeopathy hospitals near me
Homeopathy hospitals near me

Susan said...

Thanks for taking the time to discuss this, I really feel strongly about it and love learning extra on this topic. Celebrity net worth is a website which reports estimates of the total assets and financial activities of celebrities. Read it for more information.