All about Commas...

[Continued from last week]

Using Commas after a Transitional Phrase

A transitional phrase is a term like However, Therefore, and As a result. (There are others, but these are the most common.) A transitional phrase is usually at the start of a sentence and acts like a bridge to a recently mentioned idea (often an idea in the preceding sentence). A transitional phrase is usually followed by a comma.

For example:

John has eaten at least two cakes a day for the last decade. As a result, he has been placed in a high-risk group for diabetes.

I think. Therefore, I am. Rene Descartes (1596-1650)

A transitional phrase is never preceded by a comma. You can, on occasion, precede it with a semicolon (or a dash replacing a semicolon), but never a comma. That's called a run-on error.

Using Commas after an Interjection

An interjection is usually a short word inserted into a sentence to express an emotion or feeling.

Expressions such as yes, phew, and indeed are examples of interjections.

Often, an interjection will sit at the start of the sentence but not always. It is normal practice to offset an interjection with a comma (or commas if it's in the middle of the sentence).

In the examples below, the interjections are shaded:

Oh great, the boiler's broken down.

Yes, that's three out of three. I understand your predicament, but, crikey, there is nothing we can do.

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Note:

If the interjection is to express a powerful emotion or feeling (and it's not in the middle of your sentence), then it can be followed by an exclamation mark.

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