SAT Writing: Punctuation Rules

Commas (,) can be used in a list, to set apart nonessential clauses, after an introductory phrase, or before conjunctions to join two independent clauses.
Example (in a list): My favorite foods are ice cream, macaroni and cheese, pancakes and string cheese.
Example (with a nonessential clause): Her Aunt Shelley, married to her Uncle Eric, had a great voice.
Example (after an introductory phrase): After the movie, I went to the late-night diner.
Example (before conjunctions): I am a good soccer player, but my sister is much better.
For commas used with a nonessential clause, you can always check to see if the clause is “nonessential” by removing it and re-reading the sentence without it. If the sentence makes sense without the clause, then the commas are okay. Commas are one of the most overused pieces of punctuation so unless they are functioning in one of the above ways, look for answer choices that get rid of them!

Semicolons (;) can be used to combine two independent clauses or to separate items in a list when the items already contain commas.
Example (combining clauses): We went up in the hot air balloon; the view from that high up was amazing.
Example (separating items): I wanted to study drawing, painting and sculpting in the Art department; French and Spanish in the Languages department; and biology, chemistry and anatomy in the Science department.
If you see a semicolon in the middle of sentence and it is not part of a list, make sure that the two clauses on either side of the semicolon are independent (meaning they form a complete sentence on their own). You cannot separate a dependent and an independent clause with a semicolon. Both must be independent!

Colons (:) are used to introduce information, commonly a list, definition or explanation.
Example (introducing a list): Here is what is in my closet: three sweaters and two pairs of jeans.
Example (introducing a definition): After school he joined the French foreign legion: a unique unit in the French army open to foreign nationals.
Example (introducing an explanation): Here is how to succeed on the SAT: learn strategies for each question type, practice as much as possible and stick to a study schedule.

Dashes (−) can be used to indicate a change in thought or to set aside nonessential information (much like the comma!)
Example (indicating a change): My favorite color is green – no, blue!
Example (with a nonessential clause): My favorite store is Sears – which is officially called Sear’s, Roebuck’s and Co. – but I also shop at Macy’s.
Make sure that two dashes are used to set apart nonessential information. Don’t set off information with dashes that is important to the understanding of the sentence.

Apostrophes (’) are used to indicate possession or to make a contraction.
Example (as possession – singular): Shirley’s scarf was bright purple.
Example (indicating possession – plural): The students’ scores were very strong.
Example (as a contraction): We won’t sleep in on Saturday.
If an apostrophe is being used to make a contraction, it always replaces one or more missing letters.
Make sure you understand the difference between “Its” and “It’s.”
“Its” is the possession form, and means “belonging to it,” so you would not need an apostrophe if you were using “its” to indicate possession.
“It’s” means “it is” or “it has” and does not show possession. If you are confused whether a sentence should have “its” or “it’s” in it, re-read the sentence with “it has” or “it is”. If it makes sense, you can use the apostrophe.
“Its’” is NEVER correct.