Comma splices
A comma splice (which is a form of a run-on sentence) is when two independent clauses are connected by only a comma (no coordinating conjunction or anything else). This is not proper English and can be corrected by either adding the coordinating conjunction (see Correct 1) or switching the comma out for a period or semicolon (see Correct 2 and 3).
Examples:
Incorrect: The girl ate pizza, she smiled.
Correct 1: The girl ate pizza, and she smiled.
Correct 2: The girl ate pizza. She smiled.
Correct 3: The girl ate pizza; she smiled.
Additional resources:
“When Words Collide” Seventh Edition, pg. 151
“When Words Collide” Eighth Edition, pg. 138
“When Words Collide” Ninth Edition, pg. 123
Run-on sentences
A run-on sentence is either missing the proper punctuation or it is simply far too long. Consists of two or more independent clauses linked together without the proper punctuation.
This can be corrected by taking the one long sentence and separating it into two or more new sentences.
Examples:
Incorrect: These kinds of sentences usually go on for quite some time and they are lacking the proper punctuation or they are just really way too overly long because no one wants to read this many words don’t you think.
Incorrect: She likes tomatoes and he like pickles and that guy likes cheese.
Additional resources:
“When Words Collide” Seventh Edition, pg. 150
“When Words Collide” Eighth Edition, pg. 137
“When Words Collide” Ninth Edition, pg. 123
Sentence fragments
Sentence fragments are not complete thoughts so cannot stand on their own. Often they are dependent clauses with no independent clause connected to them.
Example:
Incorrect: Although she likes the store.
Additional resources:
“When Words Collide” Seventh Edition, pg. 150
“When Words Collide” Eighth Edition, pg. 137
“When Words Collide” Ninth Edition, pg. 122