Grammar Tip – Punctuation with i.e. and e.g.

BizWritingTip reader: “Regarding ‘i.e.’ and ‘e.g.,’ my understanding is that they should be followed by a comma. I see these appearing in all different forms. Is my own understanding correct, i.e., with a comma following the abbreviation?”

BizWritingTip response: You are absolutely correct. Writers often ignore the necessary punctuation. The abbreviations “i.e.” and “e.g.” are considered interrupting words within a sentence and require punctuation on both sides to indicate this. You must put a comma or a bracket (parentheses) before the abbreviation and a comma after.

The abbreviation “i.e.” (from the Latin “id est” meaning “that is”) means everything that follows.

Examples (correct)
My business plans involve trips to several cities, i.e., Toronto, Montreal, Winnipeg, Saskatoon, and Calgary.
My business plans involve trips to several cities (i.e., Toronto, Montreal, Winnipeg, Saskatoon, and Calgary).

Your plans include trips to five cities. As you are including everything, you could have also written the sentence this way: My business plans involve trips to several cities: Toronto, Montreal, Winnipeg, Saskatoon, and Calgary.

The abbreviation “e.g.” (Latin for “exempli gratia” meaning “for example”) means some of what follows and perhaps other things as well.

Examples (correct)
My business plans involve trips to several cities, e.g., Toronto, Montreal, Winnipeg, Saskatoon, and Calgary.
My business plans involve trips to several cities (e.g., Toronto, Montreal, Winnipeg, Saskatoon, and Calgary).

Your plans include trips to some cities, but you are not sure exactly which ones yet. And you may also go to cities not listed.

But back to the original point. Remember, if you are going to use these abbreviations, punctuate them correctly.