Richbaub's Introduction to Middle School Grammar Book 1

E. After more than one introductory prepositional phrase, commas are more acceptable
but still optional:
Compare the following sentences:
In the corner of my bedroom I saw a large roach climbing the wall.
In the corner of my bedroom, I saw a large roach climbing the wall.
The comma in the second sentence is acceptable since there are two prepositional phrases
beginning the sentence, but is it really necessary?
F. The bottom line? After prepositional phrases at the beginning of sentences, if you can
do without a comma, don’t use one.
Never throw commas around whenever and wherever you want for no good reason. A “gut
feeling” is not a good enough reason!
(Other comma rules are more strict, like those regarding compound sentences or items in a
series, etc. Do you know some of these commas rules?)
Ultimately, good writers use a comma only when their gut feeling lines up with a grammatical
rule; otherwise, commas are to be avoided.
RICHBAUB’S INTRODUCTION TO MIDDLE SCHOOL GRAMMAR, BOOK 1
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