Day 211: Don’t place a comma between a subject and predicate, part 2.

In yesterday’s tip, we explained that a comma should not be placed between a subject and predicate, and this is true. However, if the subject ends with an appositive, interjection, or other type of phrase that is set off with commas, you will have a comma in that place. Consider this sentence.

“The man with the broken nose, which was purple with bruises, fell on the floor.”

The complete subject of the sentence is “The man with the broken nose, which was purple with bruises.” The predicate is “fell on the floor.” As you can see from the sentence, a comma is between the subject and predicate. Here’s why.

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The phrase “which was purple with bruises” is a non-restrictive phrase, and these are always set off with commas, one before the phrase and one after.

The most common error I see is a writer using the final comma but not the first comma, though both are necessary for this type of phrase.

These phrases are not essential to the meaning of the sentence and can be removed, along with their required commas. The commas, therefore, are a function of the phrase and not the subject. When we remove the phrase, we get the following sentence.

“The man with the broken nose fell on the floor.”

Now that we have removed the non-restrictive phrase and its required commas, we see that the sentence, in fact, has no comma between the subject and predicate.

Writers make another type of mistake when putting commas between the subject and predicate. The second most common error I see is the writer setting off a phrase by using commas that are not required. Consider this sentence.

“The man with the nose, that is broken, fell on the floor.”

Those two commas are not correct because the phrase “that is broken” is necessary to understanding which man we are describing. When we remove the incorrect commas, we get the following sentence, which has no commas between the subject and predicate.

“The man with the nose that is broken fell on the floor.”