Comma Controversy! Incorrect: "I swing bats, and squish spiders."

Commas are a matter of style, hence they are a never-ending, circus-like bowl of jiggly, jolly controversy. One teacher will tell you your sentence needs a comma; another will tell you to leave the comma out. That's because style manuals like MLA, Chicago Manual of Style, The Blue Book of Grammar and Punctuation, etc. have developed individual standards. Publishers and publication companies choose a style guide and stick with it.

For today, let's follow the rule used in Chicago Manual of Style, and The Blue Book of Grammar and Punctuation.

Concept A.
Incorrect: "I swing bats, and squish spiders."
Correct: "I swing bats and squish spiders."

No comma is needed for this sentence, because the "and" conjoins a combo verb (AKA compound predicate). Notice that the person doing the action (the subject) is only mentioned once, before the first verb. Today's combo verb is "swing and squish." If the subject does not appear in front of the second verb, do not use a comma.

If the person doing the action were mentioned before both verbs, you could use a comma, as in:

Concept B.
Correct: "I swing bats, and I squish spiders."

On the other hand, although we usually use a comma to separate two clauses joined by a coordinating conjunction ("and"), some editors will tell you not to use a comma for Concept B, because you can omit the comma if the clauses are both short. So, I should have written,

Concept B. (Take Two)
Correct: "I swing bats, and I squish spiders."
Also Correct: "I swing bats and I squish spiders."