Don’t separate the subject and verb with a comma
The comma is the most misused piece of punctuation. Commas are flexible to an extent, but there are several general rules that govern their usage. In this post, I tackle a very common comma mistake: separating the subject and the verb with a comma.
While comma usage is technically a matter of style, not grammar, separating the subject from its verb with a comma is usually considered an error and should be avoided. Consider the following example:
Tony, owns an Italian restaurant.
Here, a comma separates the subject, Tony, from the verb, owns. Thus, the sentence should be revised to “Tony owns an Italian restaurant.”
Some common mix-ups
Splitting the subject and the verb with a comma is particularly common when the subject has a dependent element attached to it:
The girl who finished first in her gymnastics tournament and second in the track meet, is also a straight-A student.
The subject in this example is girl, but it’s modified by a lengthy dependent clause (“who finished first in her gymnastics tournament and second in the track meet”). However, the verb, is, is still separated from its subject with a comma. I think writers add this comma because they assume the reader needs to take a breath before reading the rest of the sentence. The idea that commas represent pauses is mostly a myth, and in this case, there should no comma between the subject and the verb:
The girl who finished first in her gymnastics tournament and second in the track meet is also a straight-A student.
A comma can only come between a subject and its verb when setting off a parenthetical or non-restrictive element. Here’s an example:
Doug, my sister’s husband, owns a car dealership.
Note that in the above example, the commas come in a pair, so the rule of thumb is to never let an odd number of commas come between a subject and its verb.
Keep a close eye out for commas that separate the subject and the verb. If your subject is long or contains a lengthy dependent element, avoid a common comma mistake and resist the urge to put a single comma before the verb.