punctuation - Should "So", "Therefore", "Hence", and "Thus" be followed by commas?

23
2014-04
  • Lone Learner

    Often, I have come across sentences that begin with "So". Should such an usage of "So" be followed by a comma?

    Are the following examples correct.

    1. He is very good at computers. So, I think he can fix your computer.

    2. When we multiply an even number with another even number, the result is an even number. So, the square of an even number is an even number.

    What happens if we choose to use "Therefore", "Hence", or "Thus" instead of "So"? Do the rules still remain the same?

    1. When we multiply an even number with another even number, the result is an even number. Therefore, the square of an even number is an even number.

    2. When we multiply an even number with another even number, the result is an even number. Hence, the square of an even number is an even number.

    3. When we multiply an even number with another even number, the result is an even number. Thus, the square of an even number is an even number.

  • Answers
  • horatio

    The short answer is "no." The longer answer is: a comma is not a requirement but neither is it something to avoid.

    What may blow your mind is that the comma is not required anywhere in any of your examples. It is a matter of style.

  • John Lawler

    Commas are not determined by grammar or by which words they follow. Comma indicates a particular intonation. If you would use that intonation in speaking the sentence, use a comma; if not, don't. So it's important to hear what you're writing, in your mind if nowhere else.

    Generally in short sentences you wouldn't, but if the sentence following the introductory word is long, you might well. Also generally speaking, if the material coming first is long (as it is in this sentence but wasn't in the previous sentence), you would.

    Punctuation is not absolute; it's a work in progress.


  • Related Question

    punctuation - "If" with implicit "then" question: Should a comma be used?
  • Michael Goldshteyn

    Consider the following phrase:

    If the fruit is an apple, it should be given to children.

    Is the comma after apple necessary? Is it optional? Is it wrong?


  • Related Answers
  • b.roth

    In that case, the comma is optional. According to the Wikipedia page on Comma:

    In English, a comma is generally used to separate a dependent clause from the independent clause if the dependent clause comes first: After I brushed the cat, I lint-rollered my clothes. (Compare I lint-rollered my clothes after I brushed the cat.)

    (..)

    While many style guides call for commas, many authors omit them, particularly with short sentences.

    The two paragraphs that I extracted from the article apply to your sentence. It's a short sentence with a dependent clause (if the item is an apple) and an independent clause (it should be given to children), where the dependent clause comes first.