10.3 Subject and object complements

Understanding Complements in Sentences

A complement is a word or phrase that completes the meaning of a verb. Without it, the sentence would feel unfinished or wouldn't make sense. There are two main types: subject complements, which describe the subject, and object complements, which describe the direct object.

Knowing the difference between these two helps you understand how sentences are built and makes your own writing clearer and more precise.

Subject Complements

A subject complement follows a linking verb and describes or renames the subject of the sentence. It answers the question what is the subject? or what is the subject like?

There are two kinds:

• Predicate nominative: a noun or pronoun that renames the subject. "She is a doctor." ("Doctor" renames "she.")
• Predicate adjective: an adjective that describes the subject. "The flowers smell sweet." ("Sweet" describes "flowers.")

The key ingredient is the linking verb. These verbs don't show action; they connect the subject to the complement. Common linking verbs include:

• Forms of "to be": is, am, are, was, were
• Sensory verbs: look, smell, taste, sound, feel
• State-of-being verbs: appear, seem, become, remain

A quick test: if you can replace the verb with "is" or "are" and the sentence still makes rough sense, you're probably dealing with a linking verb and a subject complement. "The soup tastes delicious" → "The soup is delicious." That works, so "delicious" is a subject complement.

Object Complements

An object complement follows a direct object and describes or renames that object. It completes the meaning of certain transitive verbs that would feel incomplete with just a direct object alone.

Like subject complements, they come in two forms:

• Noun as object complement: "The committee elected her chairperson." ("Chairperson" renames "her.")
• Adjective as object complement: "The chef made the sauce spicy." ("Spicy" describes "sauce.")

Object complements appear after specific types of transitive verbs:

• Causative/naming verbs: make, name, elect, appoint, call
• Perception/opinion verbs: consider, find, think, believe

Notice that without the object complement, these sentences lose important meaning. "The committee elected her" is grammatically complete, but "The chef made the sauce" leaves you wondering: made the sauce what?

Comparing and Applying Complements

Subject vs. Object Complements

The core difference comes down to which verb type is involved and what the complement describes:

To figure out which type you're looking at, follow these steps:

1. Find the verb. Is it a linking verb or a transitive verb?
2. If it's a linking verb, the word that describes the subject after it is a subject complement.
3. If it's a transitive verb, find the direct object first. Then check if there's a word after it that describes or renames that object. If so, that's an object complement.

Using Complements Effectively

Complements give you tools to write with more variety and precision:

• Subject complements let you describe a subject's qualities or identity without adding extra clauses. "The night grew cold" is tighter than "The night changed and it became cold."
• Object complements pack extra information into a single clause. "The news made everyone anxious" says in one sentence what might otherwise take two.

A common mistake is confusing complements with other sentence parts. For example, in "She called her friend," "friend" is a direct object. But in "She called her friend unreliable," "unreliable" is an object complement describing "friend." The structure around the word determines its function.

When proofreading, identify the verb first. That tells you whether to expect a subject complement, an object complement, or neither.