Sentence Parts and Parts of Speech Part 3: What are Subjects, Predicates, Objects, Complements, and Modifiers?

What are the separate parts that make up individual sentences? You might not know all the answers to this question, but you also might not know the point of learning sentence parts. Here’s the thing: understanding the separate parts of a sentence can help you learn how those parts function together, how they are initially constructed and strung together, and how this overall structure impacts the meaning of the sentence. Furthermore, understanding the terminology used to describe sentence parts will give serious writers a stronger grasp of writing advice that uses such language.

This blog post comprises Part 3 of a multi-part series on sentence parts. This particular post will focus primarily on subjects, predicates, objects, complements, and modifiers, including definitions and examples.

If you haven’t already, be sure to check out Part 1, which focuses on words, phrases, and clauses, and Part 2, which focuses on parts of speech. 

Sentence subjects: Simple, complete, and compound subjects

Sentence subject definition | A subject is the main person, place, thing, or idea a clause is about. (Part 1 of this blog series defines “clause.”) The subject is the answer to the question, “Who or what is this clause about?” Both dependent and independent clauses contain subjects. Subjects are usually nouns or noun phrases, or they are other parts of speech acting as nouns.

Sentence subject examples: 

• Sam’s car is blue.
• Sam’s sleek, blue car drives slowly through the streets of downtown. 
• Sam’s car is blue, but his wife’s car is red.
• Although Sam wants an electric car, he owns a fuel-powered vehicle.
• Sam drives through the downtown district while various patrons bustle through the streets.

Simple subject definition | A simple subject is an unadorned subject, which is a subject without any modifiers. (Scroll down for the definition of “modifier.”) Usually, a simple subject is made up of a single word, but sometimes, multiple words can make up a simple subject if those words equally name the subject (such as a first and last name together). 

Examples of simple subjects: 

• Sam drove. 
• Sam Anderson drove. 
• While the policeman waited under the bridge, a car sped past. 

*Note: grammar sources use the term “simple subject” in contradictory ways, espousing two different views. View #1 considers the definition of simple subject to be a subject that does not have modifiers, which means that not all sentences will have simple subjects. View #2 considers every complete sentence to have a simple subject, stating that the simple subject can be found by stripping the subject of its modifiers if it has modifiers. Consider this sentence: “The angry man stormed off.” The first view would say that this sentence does not contain a simple subject, while the second view would say that “man” is the simple subject. I promote the first view, but if you are reading this blog post because you are a student who needs help understanding this concept, make sure that you understand your instructor’s view on this topic. 

Complete subject definition | A complete subject contains modifiers and is considered to be the subject and its modifiers together. In other words: the complete subject contains the simple subject and all the other information that “completes” that subject. 

Examples of complete subjects:

• The white-bearded man stopped his car. 
• My friend Laini came over.
• The loud, iridescent purple car sped past.
• The man from Texas grew frightened because the French bulldog growled at him. 

Compound subject | A compound subject is made up of two or more simple and/or complete subjects; these subjects are joined by a conjunction. 

Compound subject examples:

• The boy and girl from Texas waved hello. 
• Neither the rowdy dogs nor the meowing cats noticed the duck. 
• Ice-cream cake or blackberry pie will be well received at the banquet. 

Sentence predicates: Simple, complete, and compound predicates

Predicate definition | While a subject is who or what a clause is about, the predicate is what completes the rest of the clause.  A predicate tells us what the subject of a clause is doing or being, and it may include additional information, as well. A predicate always contains a verb (for more on verbs, see Part 2 of this blog series). 

Examples of predicates: 

• Sam’s car is blue.
• Sam’s sleek, blue car drives slowly through the streets of downtown. 
• Sam’s car is blue, but his wife’s car is red.

• Although Sam wants an electric car, he owns a fuel-powered vehicle.
• Sam drives through the downtown district while various patrons bustle through the streets.

Simple predicate definition | A simple predicate is a predicate containing only a verb. Because of this, any verb in a simple predicate will be an intransitive verb (which is a verb that isn’t required to take a direct object, as compared to a transitive verb, which is required to take a direct object). 

Simple predicate examples:

• Sam drove.  
• His wife slept.

*Note: grammar sources also use the term “simple verb” in contradictory ways, espousing two different views. View #1 considers the definition of simple predicate to be a predicate containing just a verb and no modifiers, which means that not all sentences will have simple predicates. View #2 considers every complete sentence to have a simple predicate, stating that the simple predicate can be found by stripping the predicate’s main verb of its modifiers if it has modifiers. Consider this sentence: “The man ate his cake quickly.” The first view would say that this sentence does not contain a simple predicate, while the second view would say that “ate” is the simple predicate. Again, I promote the first view, as can be seen by the definition provided up above, but if you are reading this blog post because you are a student who needs help understanding this concept, make sure that you understand your instructor’s view on this topic. 

Complete predicate definition | A complete predicate contains more than just the verb; it comprises the verb and everything else that completes information about what the subject is doing or being, such as modifiers, objects, and complements. 

Complete predicate examples:

• Sam hesitantly gave her the keys to his car.
• Sam’s brand new airbags ejected from the dashboard with explosive power.
• Sam looked terrified after his accident. 

Compound predicate definition | A compound predicate contains multiple verbs connected to the same subject. These verbs are connected by conjunctions. 

Compound predicate examples: 

• The brakes shuddered and screeched.
• Sam stepped on the gas and drove quickly. 

Sentence objects: Direct objects, indirect objects, and objects of prepositions

Object definition | An object is a person, place, thing, or idea that is affected by the verb in the predicate. A noun, pronoun, noun phrase, or noun clause comprises an object. (For more on noun phrases and noun clauses, see Part 4 of this blog series, which is forthcoming.) 

Direct object definition | A direct object is directly affected by an action verb in the predicate. Because of this, it usually comes after the action verb. 

Direct object examples:

• Sam drove his car.
• He dropped off his wife.

Indirect object definition | An indirect object is the “who” or the “what” that the action of the verb is to or for. 

Indirect object examples: 

• Sam gave me his car. 
• Sam lent his car to his wife. 

Object of preposition definition | Objects can also be taken by prepositions. An object of a preposition is the who or what that works with a preposition in a prepositional phrase.

Examples of objects of prepositions: 

• Sam drove his car under the bridge. 
• Sam drove his car into a pole.

Sentence complements: Subject complements, object complements, and more

Complement definition | Complements complete the meaning of another part of the sentence by renaming or describing something about that part of the sentence. These elements are necessary to the sentence, as deleting them would result in an ungrammatical sentence or a sentence with different grammar (i.e., grammar that creates a different meaning). Parts of the sentence that can have complements include the subject, object, verb, adjective, adverb, and preposition. I won’t go into too much detail about these, especially since “complement” appears to be becoming a less-favored grammar term, but some examples are included below. 

Subject complement definition | A subject complement renames or describes the subject. Subject complements are sometimes called predicate nouns or predicate adjectives. The difference between a subject complement and a direct object is that a subject complement renames or describes the subject while a direct object instead shows what is affected by the action of the subject. While objects often come after action verbs, subject complements usually come after linking verbs (such as be, become, seem, and feel).

Subject complement examples:

• Sam became a racing driver. ←Here, Sam is renamed “a racing driver,” a phrase which functions as a predicate noun.
• Sam is very capable. ←Here, Sam is described as “very capable,” a phrase which functions as a predicate adjective. 

Object complement definition | An object complement renames or describes the direct object. 

Object complement examples: 

• Sam’s wife calls him “honey.”
• The police deemed Sam a reckless driver.
• The accident made Sam angry.

For more information on all types of complements, visit this great resource from the Farlex Grammar Book. 

Modifiers: The describers of sentences

Modifier definition | A modifier is a word, phrase, or clause that describes another word or group of words. For example, a word or group of words that describes a sentence’s subject is considered to “modify” that subject. While some modifiers aren’t essential to the meaning of the sentence, others are. Many types of words, phrases, and clauses can act as modifiers: adjectives, adverbs, adjective phrases, adverbial phrases, prepositional phrases, adjective clauses, and adverbial clauses. Learn more about the different types of phrases and clauses in Part 4 of this blog series (forthcoming)!

Examples of modifiers: 

• That beautiful car is very expensive. ← In this sentence, the adjective “beautiful” modifies the noun “car.” The adverb “very” modifies the adjective “expensive.”
• [Because he crashed [into the statue] [that looks like a banana],] Sam totaled his [ridiculously expensive] car. ←The adjective clause “that looks like a banana” modifies the noun phrase “the statue.” The prepositional phrase “into the statue” modifies the verb “crashed.” The adverbial clause “because he crashed into the statue that looks like a banana” modifies the main clause “Sam totaled his ridiculously expensive car.” And the adjective phrase “ridiculously expensive” modifies the noun “car.” 
• His engine purrs like a cat. ← The adverbial phrase “like a cat” modifies the verb “purrs.” 

Don’t get too caught up in the different types of phrases and clauses just yet; the most important thing is to know that modifiers modify or describe.

Modifiers, along with subjects, predicates, objects, and complements, are just some of the parts that make up sentences. All complete sentences contain a subject and predicate, and predicates often include objects or complements. As seen above, subjects and predicates can contain any number of modifiers.

Now that you understand these sentence parts, you can use this information to construct or deconstruct sentences, and you can benefit from writing advice that uses this terminology. Check out my blog post “Playing With Sentence Subjects: Three Creative Writing Tips for Improving Sentence Variety,” which uses some of the lingo discussed in this post!  

I hope you found this blog post helpful! Feel free to share your thoughts below. 

And stay tuned for Part 4 of this multi-part blog series, which will discuss how phrases and clauses can function as parts of speech.