No Comma for Short Introductory Words or Word Groups Acting as Simple Modifiers
The Comma
Rulebase Summary
Do not use punctuation for a single word or short word group at the beginning of a sentence that acts as a simple modifier, usually adverbial. Use a comma for long word groups — the cutoff is generally four or five words — that act as simple modifiers at the beginning of a sentence. These rules apply to simple modifiers only, not parentheticals, neutral remarks, or clauses.
Examples
A. Recently, he has not been himself.
A. Recently he has not been himself.
Short simple modifier — no comma needed.
A. Early the next Monday morning he came in to confirm it.
A. Early the next Monday morning, he came in to confirm it.
Long word group (five words) as simple modifier — comma needed.
Transcript Notes
The distinction is between simple modifiers and parentheticals or other elements. Simple modifiers do not need a comma when they are short; they do when they are long. Parentheticals, neutral remarks, interjections, and similar elements always take punctuation regardless of length.
Gregg's is more permissive than Morson's and BGGP on this point — it allows a comma after short introductory prepositional phrases when the comma aids readability. In court reporting, follow Morson's/BGGP unless local style dictates otherwise.
Style Guide References (2)
BGGP
BGGP