The Farlex Grammar Book > English Grammar > Syntax > Subjects and Predicates > The Predicate > Complements > Subject Complements
What is a subject complement?
A subject complement is the information that follows a linking verb to describe, identify, or rename the subject of the clause. Whereas most verbs describe the action a subject performs, linking verbs describe something about the subject, which is completed by the subject complement.
A subject complement can either be a predicate noun, a predicate pronoun, or a predicative adjective.
Nouns that follow linking verbs are known as predicate nouns (or sometimes predicative nouns or predicate nominatives). These serve to rename or re-identify the subject. If the noun is accompanied by any direct modifiers (such as determiners, adjectives, or prepositional phrases), the entire noun phrase acts predicatively.
- “Love is a virtue.” (The noun phrase a virtue follows the linking verb is to rename the subject love.)
- “Tommy seems like a real bully.” (The noun phrase a real bully follows the linking verb seems to rename the subject Tommy.)
- “Maybe this is a blessing in disguise.” (The noun phrase a blessing in disguise follows the linking verb is to rename the subject this.)
Predicative noun clauses
Noun clauses are dependent clauses that are able to function grammatically like nouns in a sentence. They most commonly begin with the words that, how, if, and the “wh-” words—what, whatever, where, wherever, when, whenever, why, which, whichever, who, whom, whoever, whomever, whether, and whatever.
Because they behave like nouns, they can perform all the roles that a normal noun would fill in a sentence, including as a subject complement. For example:
- “Japan is where I want to go most.” (Where I want to go most is the predicate noun of the linking verb is, renaming the subject Japan.)
- “The thing I wish for most is that people would all just get along.” (That people would all just get along is the predicate noun of the linking verb is, renaming the subject the thing I wish for most.)
- “Politicians are who create the laws.” (Who create the laws is the predicate noun of the linking verb are, renaming the subject politicians.)
We can also use a predicate pronoun after a linking verb to re-identify the subject. This is most common in questions and responses in which the identity of the subject is not known or is being explained. For example:
- Question: “Who is it?” (The pronoun it follows the linking verb is to rename the subject who.)
- Answer: “It’s me!” (The pronoun me* follows the linking verb is to rename the subject It.)
We also commonly use personal pronouns in the possessive case predicatively, as in:
- “That’s mine.”
- “The computer was his.”
- “Victory is ours!”
We can also use subjective* personal pronouns in declarative statements, but this is less common in everyday speech and writing, as it tends to make the sentence sound more formal than is usually necessary. For instance:
- “It was I who did this.”
- “Her husband took all the credit, but it was she who did all the work.”
- “It was they who assured us that there would be no problems.”
*The subjective case
When pronouns that are not possessive are used predicatively, the conventional rule is to put them in the subjective case rather than the objective case. Pronouns in the objective case (me, us, him, her, them, whom, and whomever) should only be used as direct objects of verbs or prepositions, not as subject complements.
For example, “it was I who did this” is more correct than “it was me who did this.”
In conversational English, however, this distinction is much less frequently observed, and you will often hear people using phrases such as “it’s me” or “that was her” in response to questions.
But in writing (especially formal or professional writing), always use the subjective case for a personal pronoun if it is functioning as a subject complement after a linking verb.
A predicative adjective is an adjective used after a linking verb to describe or modify the subject of the clause. For example:
- “You look nice.”
- “He is very handsome.”
Here, nice describes the subject you, while the adjective phrase very handsome describes the subject he.
Note that adjectives appearing immediately before the noun they are describing are known as attributive adjectives. For example:
- “The old man seems nice.”
Old is an attributive adjective that describes the subject, man. Nice also describes man, but it is a predicative adjective because it follows the linking verb seems.
Prepositional phrases can either functions as adjectives (modifying nouns or pronouns) or adverbs (modifying verbs, adjectives, and adverbs). When a prepositional phrase follows a linking verb (especially the verb be), it is functioning in the same way as a predicative adjective, describing the subject (which must be a noun or pronoun). For example:
- “The cat is in the shed.” (The prepositional phrase in the shed is describing the subject the cat.)
- “I am across the street.” (The prepositional phrase across the street is describing the subject I.)