Addressing series of three commas in a tutoring session

Series of three commas can be a wonderful first success for students when learning to find their own grammar errors. For some reason, students habitually miss these commas but are quick to learn to see and correct them. The first time the error occurs, the tutor can say, “You have a series of three in this sentence. Where should you put commas?” If the student doesn’t know, I like to teach them this phrase: The American flag is red, white, and blue. I actually say the word “comma” as I write and say the sentence aloud. Then I say, by contrast, the Canadian flag is red and white, no commas! I reiterate that in a series of two there are no commas but in a series of three there are commas. Series of three will show up in many ways: nouns, verbs, adjectives, even adverbs. But it doesn’t matter what type of words they are, the students can tell that they have three of something and that they need to put the appropriate commas in. The next time series of three comes up in the paper, the tutor can simply say “I spy a series of three that needs its commas fixed” and students jump at the chance to find and fix them.