mkinde wrote:On page 665 of OG13, under the Agreement title, examples of non-verb agreement correct and incorrect structures are provided. I am having trouble identifying the subjects of the following sentences and how to determine if the subject is plural or singular. Can someone pleas provide detailed explanation on how to breakdown the sentences?

Correct: "The number of residents has grown."
Incorrect: The number of residents have grown."

You can use meaning to determine what the subject is. In this case, the residents themselves have not grown. The number of residents has grown. So number is the subject.

This sentence is different. In it the children themselves have grown.

A number of the children have grown over two inches in just one year.

So in some cases number itself is the subject, in which cases you need a singular verb. In other cases, number is an indefinite pronoun and is combined with something to create a plural subject.

The number of children - number is the subject. - singular

A number of children - number of children is the subject.(basically) - plural

Here is some more on this.

https://www.grammar-monster.com/lessons/ ... number.htm

Correct: "The masses have spoken."
Incorrect: "The masses has spoken."

masses is the plural subject.

Here is a simple solution to your problem. In this one
Correct: "The number of residents has grown."
Incorrect: The number of residents have grown."

"The number of residents has grown" is the correct answer because of this rule. (A subject will come before a phrase beginning with of. This is a key rule for understanding subjects. The word of is the culprit in many, perhaps most, subject-verb mistakes.)

On the second one
Correct: "The masses have spoken."
Incorrect: "The masses has spoken."

"The masses have spoken." is the right answer because "masses" is the subject. The basic Rule says (A singular subject (she, Bill, car) takes a singular verb (is, goes, shines), whereas a plural subject takes a plural verb.)