Punctuation Guide: Apostrophes, Quotation Marks, and End Punctuation

Periods (.) are placed at the end of a fact or an opinion sentence

• Jane and Jack went up the hill.
• The weather has been very pleasant this week.

Use a question mark (?) to indicate a direct question when placed at the end of a sentence.

• When did Jane go up the hill?

The exclamation point (!) is used when a person wants to express outcry or add emphasis.

• "Holy cow!" screamed Jane.
• Jack's rants make me furious!

More than one punctuation at the end of a sentence

If there is more than one punctuation at the end of the sentence, do not use a period. 

• I finally saw Who's Afraid of Virginia Woolf?
• Their dream is to work at Yahoo!

Punctuation and Parentheses

Punctuation goes on the outside of the closing parenthesis.

• We are hopeful that the Library reopens soon (assuming that Covid numbers continue to fall). 

If the entire sentence is in the parentheses, the punctuation goes inside. This is rare in academic writing.

• The entire story was dark and gloomy. (Some may argue that this adds to the allure.)

Quotation Marks and Punctuation

With quotation marks, the period goes on the inside of the quotes

• One of the hallmarks of the speech is the repeated word "freedom."

If there's a different punctuation mark on the inside of the quotes, do not add a period.

• The madman kept repeating, "Don't you hear the sound of the heartbeat?"

Apostrophes (') are used in contractions (words made by shortening and combining two words)

• can't (can + not)
• don't (do + not)
• I've (I + have)

*Some instructors may prefer no contractions in research papers. 

Apostrophes are used to indicate possession or ownership

For singular nouns add apostrophe and s ('s).

• Tim's lunch
• the flower's petals
• 2020's pandemic (here the year 2020 is a possessive noun)

For plural nouns that end in s just add the apostrophe ( ' )

• the pigs' barn
• the couples' secrets

Exceptions:

When a noun ends in an "us" or "eez" sound 

• Amadeus' piano 
• Socrates' philosophy

It's and Its

It's is a contraction of it and is.

• It's a great day to ride a bike. (It is a great day to ride a bike.)

Its is a possessive form of it. 

• My bike is old and its brakes need to be fixed. (The brakes belong to the bike which is the "it".)