Example 1

Incorrect: To pass calculus you must be able to evaluate limits.

Correct: To pass calculus, you must be able to evaluate limits. 

Explanation: One needs to separate the independent clause from the dependent clause with a comma.

Example 2

Incorrect: The boys look for the missing comma. Meanwhile the clock strikes at 2 am.

Correct: The boys look for the missing comma. Meanwhile, the clock strikes at 2 am. 

Explanation: One needs a comma after introductory phrases like "meanwhile." 

Introductory commas are used:

• With long introductory prepositional phrases 
• After an introductory clause 
• After introductory verbal phrases 
• If there is a distinct pause   

When not to use Introductory Commas:

• After a brief prepositional phrase of five words or less 
• After a noun phrase 
• To separate the subject from the predicate  

The following may seem like they need a comma at the (x), but they do not:

Getting up at 9am to go to CASA(x) was one of the hardest things for Bill to do. 

To start studying for a math exam 15 seconds before class(x) would be very foolish.

Doing your homework to practice material(x) is the purpose of homework altogether. 

Commas and Introductory Elements

Commas for Introductory Phrases and Clauses

Introductory commas follow an introductory phrase. This means that when the dependent clause comes before the subject in the sentence, you must add a comma. These commas are important to avoid confusion. 

Fall 2019

Calen Frongillo, Framingham State U, Class of 2023

Alex Portanova, Framingham State U, Class of 2023

Matthew Finn, Framingham State U, Class of 2023

Works Cited

"Commas after Introductions." Purdue Online Writing Lab, owl.purdue.edu/owl/general_writing/punctuation/commas/commas_after_introductions.html.

"Commas and Introductory Elements." Khan Academy, www.youtube.com/watch?v=NvGBug8iORE&feature=youtu.be. 

"Commas for Introductory Phrases and Clauses." Matt Mullan, www.youtube.com/watch?v=Ae4YWFwmWPI.