Monday, July 25, 2011

Grammar Brigade: Clauses, and why they matter

What's a clause?

A clause is a group of words which contains both a subject and a verb. 
ex: He walks.
ex: while I ran
ex: if you look under the couch

Sometimes, clauses have implied subjects.  That's okay, too - they still count as clauses.
ex: Don't do that!  (implied subject: person addressed)
ex: Run!  (implied subject: person addressed)
ex: don't worry (implied subject: someone who should probably be worried)

Note: Clauses with implied subjects are different from interjections.  Interjections are one-word expressions, usually showing emotion.  They can stand alone, or be added to a sentence.
ex: Oops.  (not a clause!)
ex: Wow!  (not a clause!)

Clauses come in two types: independent and dependent. 

An independent clause is a clause that is, in and of itself, a sentence.  It can stand on its own, although you might want to add more to it.
ex: He runs.
ex: He throws a Frisbee at Mike.
ex: Mike dodges the ninja star disguised as a Frisbee.

A dependent clause is a clause that cannot stand on its own.  By itself, it is just a sentence fragment.  It is preceded by a conjunction or a marker word.
ex: because Mick didn't move fast enough
ex: when Mick dodged
ex: if I do a cartwheel

Dependent clauses must be tacked on to independent clauses in order to be a full sentence (They're kind of needy that way.)  This usually requires punctuation, in the form of a comma, unless one of the clauses is particularly short.
ex: When Mick ran for president, I voted for the other guy.
ex: If I do a cartwheel, I will break my neck.
ex: I'll bake the cake, while you make the icing.
ex: I laughed when Susan dropped flour on Mick.  (I laughed/ when Susan dropped flour on Mick) ("I laughed" is short - no comma is needed in this case!)

Independent clauses may be joined together to form a full sentence, but they require either the addition of conjunctions (and, so, but, yet, for, nor, or), or the use of a semicolon.
ex: I walked to the store, but Mick ran.
ex: I walked to the store; Mick ran.
ex: I planted a gardenia outside, and now my yard smells nice.
ex: I planted a gardenia outside; now my yard smells nice.

Some common words can be added to independent clauses without removing their independent status.  Some of these are words like: however, moreover, also, nevertheless, furthermore.
ex: I walked to the store; however, Mick ran.  (Still need that semi-colon!)
ex: I planted a gardenia outside; nevertheless, my yard still smells like fish.

If you combine two independent clauses with a comma, then you have a comma splice.  This is a type of run-on sentence, and your paper will bleed red when your editor returns it to you.
NO!:  I walked to the store, Mick ran.  :NO!
NO!:  I planted a gardenia outside, now my yard smells nice.  :NO!
NO!: I planted a gardenia outside, nevertheless, my yard still smells like fish.  :NO!

Be supportive for your dependent clauses.  Give them the punctuation they need in order to survive an editor's brutal attack.

(Thanks to Purdue OWL for definitions!)

This Grammar Brigade attack is brought to you by... common comma errors!

Do you have a grammar question?  If I don't know the answer, I'll look it up!


  1. That vs. which would be a good one to go over. I've had "which-hunting" beaten into my head so much that I barely use it at all in scientific writing...but I like the way it sounds and I don't want to miss a place where it's actually correct.

  2. Great idea! I didn't really understand that rule until well after college. I'll add that to the queue. ;)