Parts of a Sentence

Sentences are the building blocks of our written language. In order for sentences to actually be effective, they must be built in a specific manner. One aspect of building sentences is agreement. Basically, agreement refers to specific types of words that must match, or agree with, other types of words.

However, in order to learn about agreement between words, we need to first review the parts of a sentence. You have probably already learned that a sentence is made up of a subject and a predicate. The subject is the main noun doing the action, and the predicate is the verb and the words that follow.

Also, you have most likely learned that a noun is a person, place or thing, and a verb is the action word in the sentence. These are very basic definitions for these terms, but this is all we need to explore agreement in sentences. Now that we have reviewed these ideas, let’s look at how each term must agree within a sentence.

Subject-Verb Agreement

One of the most important concepts you have to know in order to build sentences is subject-verb agreement. Subject-verb agreement is the rule that all verbs must agree or match the subject. Simply put, if the subject is singular, you must use the verb that matches. If the subject is plural, there is a different verb to match it.

Singular Subjects

If you think you may have made an error in subject-verb agreement, check to see if your subject is singular. Then make sure your verb matches. Look at this sentence:

• Mike has decided to only play basketball this year.

First, identify your subject and the verb. What is the main noun doing the action? Mike is the subject. Now what is the action Mike is doing? In this sentence, Mike ‘has decided’, so that whole verb phrase is the main action. When this occurs, you only have to worry about agreement with the first part of the verb phrase. So, since the subject, Mike, is singular, in order to make your subject and verb agree, ‘has’ must also be singular. Do not use ‘have’, which is the plural form of the verb.

Plural Subjects

Now let’s look at agreement with a plural subject.

• Mike and David have decided to only play basketball this year.

In this sentence, the subject is no longer one person. Both Mike and David are completing the action and both are the subject of the sentence. In this case, you must use the plural form of the verb, which is have.

This holds true for any type of word that is plural when it is functioning as the subject of the sentence. For instance, the pronoun ‘we’ is plural and so must have a plural verb to match. Look at the difference in subject-verb agreement in the following sentences. Try to identify the singular and plural subjects and verbs.

• The dog runs down the street every day. (The subject ‘dog’ is singular. The verb ‘runs’ matches.)
• The dogs run down the street every day. (The subject ‘dogs’ is plural. The verb ‘run’ matches.)
• He jumps over the fence all the time. (The subject ‘he’ is singular. The verb ‘jumps’ matches.)
• They jump over the fence all the time. (The subject ‘they’ is plural. The verb ‘jump’ matches.)

Separated Subjects and Verbs

A common error in subject-verb agreement occurs when words or phrases separate the subject and the verb. All our examples so far have had the subject and verb next to each other. But look at this sentence:

• Mike and David, who both played football and basketball last year, have decided to only play basketball this year.

In this case, we have the phrase, ‘…who both played football and basketball last year,’ separating the subject and the verb. The subject, Mike and David, is plural and still must match the plural form of the verb ‘have.’ Make sure you can find the correct subject of your sentences when you check for agreement. This might be difficult at times. Look at one more example and try to identify the true subject and the verb.

• The fact that Molly didn’t study for the test prevents her from getting an A. (‘fact’ is the singular subject, which matches the singular form of the verb ‘prevents’)

The key to avoid subject-verb agreement errors is to ignore all the extra words and match the true subject of the sentence, not just the noun that is the closest.

Adjective and Adverbs

When talking about agreement, there is one more aspect that you need to know in order to avoid errors: adjectives and adverbs must also agree with the words they modify. You should remember that an adjective is a word that modifies a noun, and an adverb is a word that modifies a verb, adjective or another adverb. Adjectives must always be matched with nouns, and adverbs must always be matched with verbs, adjectives or adverbs.

One clue that a word might be an adverb is if it ends with the suffix ‘-ly’. For example, ‘quick’ is an adjective, and ‘quickly’ is an adverb. When you use these two terms, they must match up to the right type of word. So ‘quick’ must be matched with a noun, and ‘quickly’ must be matched with a verb, adjective, or adverb. Look at these two sentences:

• Sarah is a quick sprinter.
• Sarah sprints quickly.

Why is ‘quick’ used in the first sentence, but ‘quickly’ in the second? In the first sentence, ‘quick’ is modifying the word ‘sprinter’, which is a noun. On the other hand, in the second sentence ‘quickly’ is modifying the word ‘sprints’, which is a verb. You cannot write, ‘Sarah sprints quick.’ This is the incorrect form as an adjective cannot modify a verb.

So to avoid errors with adjective and adverb agreement, be sure to think about which word you are modifying.

Lesson Summary

To review, agreement in sentences consists of several different concepts. First, you must understand all sentences must have a subject, which is the main noun doing the action, and a predicate, which is the verb and the following words. A noun is a person, place or thing, and a verb is the action word.

Subject-verb agreement states that the subject and verbs in sentences must match. This means that if the subject is singular, the verb must use the matching singular form. If the subject is plural, the plural form of the verb must be used. Remember, many times other words come in between the subject and the verb. Do not try to match the verb to any of those other words. In fact, you can ignore all the other words and pay attention to only the subject when avoiding errors in agreement.

Lastly, agreement is also important when using adjectives and adverbs. Adjectives are words that modify nouns, and adverbs are words that modify verbs, adjectives and other adverbs. When using these parts of speech, you must make them agree with the right word. For instance, the adjective ‘quick’ must be matched with a noun, and the adverb ‘quickly’ must be matched with a verb.

Remember these tips, and you will avoid all agreement errors in your own writing.