GB3: Complete Sentences


  1. Recognize elements of a sentence.
  2. Understand differences between clauses.
  3. Write complete sentences.

The core elements of complete English sentences include subjects, objects, predicates, and modifiers. Subjects and predicates are needed in order for a sentence to be “complete.” Sentences need an action and someone (or something) doing it. The action is the predicate, and the person (or thing) doing it is the subject.

Without a subject performing an action, a sentence is incomplete. Compare and contrast the sentences below:

  1. I like pizza. Because it tastes delicious.
  2. I like pizza because it tastes delicious.

Of the two examples above, the first contains a fragment: “Because it tastes delicious” is a fragment, or an incomplete thought. This is a fragment because the phrase includes an “action” (tasting delicious) but no subject.

The second example is correct; it has all the necessary components of a full sentence—a subject and a predicate. It also has a subordinate clause, because it tastes delicious, which modifies the word pizza.


The subject of a sentence is a noun or pronoun (and its article, if it has one). In active-voice sentences, the noun or pronoun performs the action in the sentence. See the italicized subjects in the examples below:

  1. The boy crossed the street.
  2. She works in the city.
  3. Mark is a good athlete.

In example 1, the subject, “the boy,” is both a noun and its article. In example 2, the subject is a pronoun. In example 3, the subject is a noun (no article).


The predicate explains the action of the sentence. Sometimes “predicate” can simply mean “everything except the subject.” The simple predicate is the action (verb or verb phrase) of a sentence.

In the examples below, the predicates are italicized:

  • The house is green.
  • She seems angry.
  • The burden became excessive.


The object of a sentence is the noun or pronoun which is being acted upon, or at which the action is directed. There are two types of objects: direct objects and indirect objects.

Direct Object

The direct object is the object which is being acted upon in the sentence. See the italicized direct objects in the examples below:

  • Johnny throws the ball.
  • Jill cuts the cake.
  • Bill rides the bike.

Indirect Object

The indirect object answers the questions “to whom/what?”or “for whom/what?” in a

sentence. It is not acted upon. See the italicized indirect objects in the examples below:

  • Johnny throws the ball to me.
  • Jill cuts the cake for her friends.
  • Bill rides the bike to school.

No Object

Some sentences do not need an object and consist of only a subject and a verb predicate. For example:

  • Mary smiled.
  • Fred sneezed.

This can happen because some verbs (like the ones above) don’t require an object. When a verb doesn’t need an object, it is called an intransitive verb.


A modifier is a phrase in a sentence that provides additional information about an element within that sentence. There are three basic kinds of modifying constructions:

  • Single-word modifiers (adjectives and adverbs): It was a nice house.
  • Modifying phrases (e.g., prepositional, participial, infinitive, and appositive phrases): Barry
  • Goldwater, the junior senator from Arizona, received the Republican nomination in 1964. (appositive phrase)
  • Modifying clauses (a clause is any group of words with its own subject and predicate): The only one of the seven dwarfs who does not have a beard is Dopey. (adjective clause)

Compound Elements

In a given sentence, there may be more than one of any of the four core sentence elements. Compound elements can include:

  • Compound subject: Mary and Tom went to the dance.
  • Compound predicate: He ran to the house and knocked on the door.
  • Compound modifier: He rode a small white pony.


A phrase is a collection of words that may have nouns or verbals, but it does not have a subject performing an action. The following are examples of phrases:

  • leaving behind the dog
  • smashing into a fence
  • before the first test
  • after the devastation
  • between ignorance and intelligence
  • broken into thousands of pieces
  • because of her glittering smile

In these examples, you will find nouns (dog, fence, test, devastation, ignorance, intelligence, thousands, pieces). You also have some verbals (leaving, smashing), but in no case is the noun functioning as a subject performing the action in the predicate. They are all phrases.


A clause is a collection of words that has a subject that is actively performing an action. The following are examples of clauses:

  • since she laughs at jokes
  • I despise individuals of low character
  • when the saints go marching in
  • because she smiled at her

Note that in the examples above, we find either a noun or a pronoun that is a subject (italicized) attached to a verb phrase (also italicized).

Independent and Dependent Clauses

If the clause could stand by itself—that is, form a complete sentence with punctuation—we call it an independent clause. The following are independent clauses:

  • I despise individuals of low character
  • Helen loves Canadian geese

We could easily turn independent clauses into complete sentences by adding appropriate punctuation marks. We might say, “I despise individuals who possess pretensions of superior learning.” Or we might write, “Helen loves Canadian geese!” We call them independent because these types of clauses can stand by themselves, without any extra words attached, and be complete sentences.

By contrast, dependent (also called subordinating) clauses cannot stand on their own. The following are dependent clauses:

  • when the saints go marching in
  • because she smiled at him
Sentence diagram
Sentence diagram 1: This diagram shows some of the component parts of a sentence, and demonstrates how they relate to each other.


Key Points

Within a sentence:

  • The subject is the noun (or pronoun) that performs the action.
  • The predicate is the verb or verb phrase that tells what action is being performed by the subject.
  • The direct object is the person or object upon which the subject is acting.
  • The indirect object answers the question “to whom/what?” or “for whom/what?”
  • A modifier gives information about a sentence element.
  • A phrase is a group of words that does not contain both a subject and a verb.
  • Sentences are made up of clauses. A clause contains at least a subject and a finite verb. A finite verb is the main verb in a sentence.

Key Terms

  • clause: Typically contains at least a subject noun phrase and a finite verb. The two main categories are independent and subordinate (or dependent).
  • modifier: A word, phrase, or clause that limits or qualifies the sense of another word or phrase.
  • object: The noun or pronoun which is being acted upon, or at which the action is directed. There are two types: direct and indirect.
  • simple predicate: The verb or verb phrase of a sentence.
  • predicate: The part of the sentence (or clause) that states something about the subject or the object of the sentence.
  • subject: In a clause, the word or word group (usually a noun phrase) that represents a person, place or thing. In active clauses with verbs denoting an action, the subject and the actor are usually the same.
  • fragment: An incomplete sentence, lacking a subject or a predicate.
  • phrase: A group of words that cannot stand on its own because it does not have both a subject and a verb.
  • complement: A word, phrase, or clause that is necessary to complete the meaning of a given expression.

Adapted from Introduction to English Grammar and Mechanics from Lumen Learning, by, used according to Creative Commons CC BY-SA 4.0

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