Use commas to separate three or more items in a series.I have mylaptop, pens, and pencilsin my backpack.They havetaken a class, studied together, and prepared well.
Use a comma to separate two adjectives when the adjectives are interchangeable.He is atall, leanman.Theold, crankycat is dying.Exception:We stayed at anexpensive summerresort (no comma because the two adjectives are not interchangeable).
Place a comma before a coordinating conjunction that connects two independent clauses.Coordinating conjunctions = FANBOYSFor, And, Nor, But, Or, Yet, SoI wantedto stay up late, but I had school the next morning.He was late to class, so his teacher marked him as tardy.
Place a comma after an introductory word or phraseCommon introductory words: however, meanwhile, still, furthermoreStill,I do not believe the defendant is guilty.Furthermore,I could not believe he was convicted.Barking incessantly,Sparky woke up the whole neighborhood.Barking incessantly = introductory participle phrase describing Sparky
Use a comma after an introductory clause. Generally, an introductory clause starts with asubordinate conjunctionand creates a dependent clause.Common subordinate conjunctions: After, although, as, while, when, until, before, because, if, sinceIfyou are not sure about this, let me know.Afterwe went to the movies, we got dinner.Beforethe sun sets, I want to go for a walk.
However, a comma is unnecessary when the dependent clause comes at the end of the sentence.Let me know if you are not sure about this.We got dinner after the movie.I want to go for a walk before the sun sets.
Use commas to set off nonessential words, clauses, andphrases.Incorrect: Jill my sister shut the door.Correct: Jill, my sister, shut the door. (We can remove “my sister” from the sentence, and the sentence still maintains the same meaning.)Incorrect: Bill Clinton the 42ndpresident of the UnitedStates is 68 years old.
Correct: Bill Clinton, the 42ndpresident of the United States, is71years old.
The deserted blue house is falling apart.The deserted blue house is falling apart.Becausewe are young we act impulsively.Because we areyoung,we act impulsively.However I am still unhappy with the outcome.However,I am still unhappy with the outcome.
We went to the store when the storm was over.We went to the store when the storm was over.John my cousin is an excellent soccer player.John,mycousin,is an excellent soccer player.The cat is friendly but the dog is quite shy.The cat isfriendly,but the dog is quite shy.
The cat however can be very annoying.Thecat, however,can be very annoying.Students who study faithfully usually do well.Students who study faithfully usually do well.Shaking violentlythe child was cold.Shaking violently, the child was cold.