Booher's Rules of Business Grammar - Dianna Booher 2009

Comma clauses and pauses
Punctuation problems

ESSENTIAL OR NONESSENTIAL—THAT IS THE QUESTION

What people do intuitively with their voice inflection often bewilders them in writing. The challenge is translating voice inflection to the page.

To be more dramatic about it: cut a comma, and you may destroy someone’s career.

To repeat: a comma tells a reader to pause. The absence of a comma means that a reader should keep going full speed ahead. If you set off the middle or final part of a sentence with a comma, you’re telling a reader that part is nonessential—that it adds information but is not essential to the meaning of the sentence.

If you can’t remove that part of the sentence without changing the meaning of what’s left, then don’t set that part off with commas.

Let’s try it: “Pudge prefers to work with clients who have multiyear contracts.”

Question: Do you need a comma to set off the who clause? Well, try the rule: Omit the final part to verify that it’s nonessential and that what’s left of the sentence has the same meaning: “Pudge prefers to work with clients.” That remaining part has a different meaning. Pudge doesn’t prefer just any clients; he’s particular. He prefers clients with multiyear contracts. “Who have multiyear contracts” is essential to the meaning of the sentence. Result: It is incorrect to set that part off with a comma.

Okay, try another example: “Brunhilda submitted our proposal, which has a strong chance of winning, to the European client last week.”

Question: Do you need commas around the which clause to set it off from the rest of the sentence? Try the rule again: omit that part to verify that it’s nonessential and to see if the meaning of the sentence changes without it: “Brunhilda submitted our proposal to the European client last week.” The meaning of what remains does not change. Result: These enclosing commas are used correctly; “which has a strong chance of winning” is additional information but nonessential to the meaning of proposal.

Consider how you would inflect your voice and where you would pause in the following sentences. (Although I’m not suggesting that you learn to punctuate by voice inflection, that system will help you determine the meaning in your own sentences and understand the use of commas to set off nonessential elements.)

Correct:

I knew the man who bought my car. (Essential: the who clause tells which man—no comma.)

Daffy signed the contract, which the client mailed overnight. (Nonessential: the which clause just adds information about the contract but doesn’t distinguish this contract from another—comma to set off.)

According to this contract, which I’ve not seen until this morning, we have 30 days to pay the invoice. (Nonessential: the which clause just adds extra information about the contract but does not distinguish it from other contracts—commas to set off.)

The emcee explained the agenda that the panel would follow during the second session. (Essential: the that clause tells which agenda—no commas to set it off.)

Here’s a rule of thumb for those essential and nonessential clauses that involve that and which:

Which clauses give nonessential information. Use commas to set them off.

That clauses provide essential information. Don’t use a comma.

Memory tip

Remember the “I think that … blah, blah, blah” model sentence.

You’d never consider it a complete idea to write or say only “I think.” Instead, you typically tell someone what you think. You think it’s too hot. You think you deserve a raise. You think Congress needs to cut taxes. The that part is essential to your “I think” sentence. A model that clause introduces essential information and needs no comma.