The subject and the verb must always agree in number. Therefore, a singular subject requires a singular verb form: The dog runs out of the house.
A plural subject requires a plural verb form: The dogs run out of the house.
Singular and plural verb forms should be second nature to you - you use them so often that there is nothing to memorize. You would never write the dog run out or the dogs runs out.
However, you may get confused when the subject is cleverly hidden in the sentence. In such a scenario, you may be unsure whether the subject is singular or plural! If you do not know the number of the subject, then you will not be able to select the verb form that agrees with the noun.
Consider this example: The discovery of new medicines were vital to the company’s growth.
If you ask yourself “What is vital to the company’s growth?” you may answer the “Discovery of new medicines is”. Therefore “The discovery... was” is correct.
The key to making subjects and verbs agree is to find the subject that goes with a particular verb. To find the subject, you must ignore all the words that are not the subject. You do that by eliminating all the non-essential information between the subject and the verb.
Generally, the subject is hidden in a few ways. The most common way to eliminate these Middlemen or Warm-ups by inserting words between the subject and the verb or putting a significant number of words in front of the subject.
This strategy will enable you to easily identify the subject and determine whether there is an error in subject-verb agreement.
WRONG: Changes for the new and improved SAT Writing section is going to be implemented soon.
Correct: Changes for the new and improved SAT Writing section are going to be implemented soon.
WRONG: When the auditors left, the executive who had been interviewed were glad.
Correct: When the auditors left, the executive who had been interviewed was glad.
Now, let’s walk through a tricky example: Mastery of magic tricks that truly (surprise/surprises) the audience (require/requires) lots of time.
Here, we have to identify the subject of two verbs.
First, cross out the warm-ups and the middlemen: Mastery of magic tricks that truly (surprise/surprises) the audience (require/requires) lots of time.
Now it’s easy to see that mastery is the main subject of the sentence. Mastery is singular, so we need the singular verb requires.
Now, let’s get back to the first verb, which is included in part of the sentence that has been crossed out. We need to ask ourselves the question “What is truly surprising the audience?” Magic tricks! Magic tricks are plural, so we need the plural verb surprise.
The correct sentence: Mastery of magic tricks that truly surprise the audience requires lots of time.
In rare instances, the subject follows the verb. In these cases, it can be particularly challenging to identify the subject and determine if there’s an error in subject-verb agreement.
Example: In the trunk of my car resides 15 empty water bottles.
In the sentence, what’s residing? The water bottles. Because the subject is “water bottles,” the verb should be in the plural form.
This is the correct version of the sentence: In the trunk of my car reside 15 empty water bottles.
The correctly written sentence may sound more awkward to you because the singular noun “car” is placed right next to the plural form of a verb. You should focus on the rules and strategies as opposed to just relying on what “sounds right.”
A common error in the agreement of subjects and verbs comes in the use of collective nouns. Collective nouns refer to groups of things or people but act, grammatically, as singular objects. If the subject of a sentence is a collective noun, the verb of that sentence should remain in its singular form.
Wrong: The firm are still making a decision on your employment status at the moment.
While “the firm” is composed of many more than two people, here the collective stands for singular grammatical entity.
Correct: The firm is still making a decision on your employment status at the moment.
As discussed in an earlier chapter, the coordinating conjunction “or,” when used to connect two nouns in a sentence, renders the subjects it connects singular. When “and” is used in this fashion, the two subjects connected are joined, and must be treated as plural.
Wrong: The umbrella or the hat are at the bottom of the stairs.
This sentence is incorrect because while “or” connects the two subjects, it also treats them both as singular entities.
Correct: The umbrella or the hat is at the bottom of the stairs.
Watch out for singular nouns ending in “s.” Just because a noun ends in “s” does not necessarily mean it is plural.
example: Mathematics is a subject that I just cannot get my head around.
This sentence is correct! The speaker is referring to one subject. He or she is not referring to many “mathematics,” just one.
A more complicated example in which a prepositional phrase is placed at the beginning of the sentence is:
Wrong: In between the cushions of my couch is change and an old pen.
What’s in between the cushions? Change and an old pen. The sentence has two subjects (change and an old pen)therefore, the verb should be plural.
Correct: In between the cushions of my couch are change and an old pen.
Hopefully, you got most of those, if not all, right. Now, try to solve the following examples.
Like subjects and verbs, related nouns in a sentence should also agree in number. When we say, “agree in number,” we mean that plural nouns most often suggest that a corresponding, logically related noun should be plural as well. The same goes for singular nouns. This is probably best illustrated with an example.
Wrong: During our panel, we came up with an answer to all the questions that were asked.
Here, it does not really make sense that “we” had a single answer to “all the questions.” These related nouns should agree in number.
Correct: During our panel, we came up with answers to all the questions that were asked.
The exception to this rule of noun-noun agreement can be found with abstract nouns, which should usually remain singular, even if they are represented by multiple objects.
Wrong: His love for his wife were shown by the many books of poems he dedicated to her.
This sentence, as you can see, reads quite oddly. While “love” and “many books of poems” are, logically related in this sentence (the “books” show the “love”), because “love” is being used here as an abstract noun to represent a singular emotional state, it must remain grammatically singular.
Correct: His love for his wife was shown by the many books of poems he dedicated to her.