Core Patterns

Subjective Complements

Some verbs do not act on anything. They link the subject to a word that names or describes it: in Her brother became a pilot, pilot names the brother’s job. That word is a subjective complement. Reed-Kellogg marks it with a backslash, and this page teaches you to tell it from a direct object.

What you’ll learn

Recognise a linking verb
Tell a predicate nominative from a predicate adjective
Draw the backslash that introduces a complement
Tell a complement from a direct object when the same verb can take either
Use an adjective, not an adverb, after a linking verb

Linking verbs and the predicate nominative

A linking verb joins the subject to a word that names or describes the subject. It does not act on anything. The main linking verb is be. Most of the others belong to two groups:

Becoming and staying: become, get, grow, turn, remain, stay.
Seeming and the senses: seem, appear, look, feel, smell, sound, taste.

The word that completes a linking verb is its subjective complement. The name says what it does: it completes the verb, and it refers back to the subject. If it is a noun, it is a predicate nominative; if it is an adjective, it is a predicate adjective. Both are drawn the same way. Spanish grammar calls this word the atributo (after ser, estar and parecer).

Try replacing the verb with 'is'
Her brother became a pilot → Her brother is a pilot. Still sensible, so became is linking here.
Check the complement refers to the subject
The pilot and the brother are the same person. In a direct object they would be different: in She bought a bicycle, she is not the bicycle.
Draw a backslash, not a half vertical
Write the complement on the base line after the verb, with a backslash in front of it. A direct object would get a half vertical there instead.

“Her brother became a pilot.”

Reed-Kellogg — the backslash leans back toward the subject

poss Possession modifier
nsubj Nominal subject
ROOT Root of the sentence
det Determiner
attr Attribute

Dependency — attr, not dobj

Comparing the two views

Reed-Kellogg shows the link by the direction of a line: the backslash leans back toward the subject, because pilot refers back to brother. A direct object would get a half vertical, which leans neither way. The tree hangs pilot from the verb, not from brother. Only its label shows the link: attr (a noun complement), not dobj (a direct object).

Predicate adjectives

When the complement is an adjective rather than a noun, nothing about the drawing changes — same backslash, same slot. What changes is the name, and the dependency label: acomp instead of attr.

An adjective can stand in two places. Before a noun, as in the cold corridor, it hangs on a slant below the noun (see Articles & Adjectives). After a linking verb, as in the corridor felt cold, it describes the subject. Then it sits on the base line, with the main parts of the sentence (see Required and optional).

“The corridor felt cold.”

Reed-Kellogg — an adjective on the base line

det Determiner
nsubj Nominal subject
ROOT Root of the sentence
acomp Adjectival complement

Dependency — acomp is a core relation

Comparing the two views

Both views make cold a main part of the sentence. Reed-Kellogg writes it on the base line, after a backslash. The tree hangs it from the verb as acomp; in the cold corridor it would hang from the noun as amod. The tree also names the kind of complement: attr for a noun, acomp for an adjective. Reed-Kellogg draws both after the same backslash.

Linking or transitive: the same verb can be both

Many linking verbs can also be transitive: they can take a direct object. The verb alone does not tell you which job it does. Look at the word after it, and ask whether it names or describes the subject, or receives the action.

The corridor felt cold. — the corridor is cold. Linking, complement.
She felt the fabric. — she is not the fabric; she acted on it. Transitive, direct object.

So decide sentence by sentence. The Practice Lab’s Verb type filter does the same: it lists felt as linking in the first sentence but not in the second. The filter appears once you sign in.

Common mistakes with linking verbs

Four mistakes are common with subjective complements. The first three come from Spanish.

Keep a or an before a job. My sister is a nurse, not My sister is nurse (Spanish: Mi hermana es enfermera).
Use be, not have, for feeling cold or hungry, and for age. I am cold and I am hungry, not I have cold or I have hunger (Spanish: Tengo frío, Tengo hambre). For age, see years old.
Choose the right -ed or -ing adjective. The -ed adjective describes the person who has the feeling: The students were bored. The -ing adjective describes what causes it: The lesson was boring. Spanish uses estar aburrido for the first and ser aburrido for the second.
Use an adjective, not an adverb. The word after a linking verb describes the subject: The chair feels comfortable, not The chair feels comfortably. An adverb would describe an action, and the chair is not doing one (see Adverbs).

Quick check

Which sentence uses grew as a linking verb, and how can you tell? Diego grew tomatoes. Diego grew tired.
Answer
Diego grew tired. Put is in place of the verb: Diego is tired makes sense, and tired describes Diego. So tired is a predicate adjective, after a backslash. In Diego grew tomatoes, Diego is not the tomatoes: he does something to them. Tomatoes is a direct object, after a half vertical, and grew is transitive there.
Find the subjective complement in each sentence. Is it a predicate nominative or a predicate adjective? My cousin became a firefighter. The streets stayed quiet.
Answer
A firefighter is a predicate nominative: it is a noun (it takes a), and it says what my cousin became. Quiet is a predicate adjective: it describes the streets, and very quiet works. Reed-Kellogg draws both after the same backslash. The tree tells them apart: attr for firefighter, acomp for quiet.
Describe the base line of a Reed-Kellogg diagram of The answer looks simple. Which words sit on it, and which marks separate them?
Answer
From left to right: answer, a full vertical that crosses the base line, looks, a backslash leaning back toward the subject, and simple. The backslash shows that simple describes the subject. A half vertical would make it a direct object, which it is not. The hangs on a slant below answer.
A classmate writes The music sounds beautifully. What is wrong, and why?
Answer
Here sounds is a linking verb: The music is beautiful makes sense. The word after it describes the subject, so it must be an adjective: The music sounds beautiful. An adverb such as beautifully would describe an action, and the music is not doing one.

Key terms

Linking verb: A verb that joins the subject to a word that names or describes the subject, instead of acting on something. The main one is be; others are become, get, grow, turn, remain, stay, seem, appear, look, feel, smell, sound, taste. Omar stayed calm. The leaves turned red.
See: Verbs & Auxiliaries
Subjective complement: The word or phrase after a linking verb that names or describes the subject: a predicate nominative or a predicate adjective. It follows a backslash on the base line. The museum was quiet. Santiago became the team captain.
Predicate nominative: A noun — or a phrase or clause doing a noun’s job — completing a linking verb and renaming the subject. Relation attr for a noun. She became a pilot. My brother is an engineer.
Predicate adjective: An adjective — or an equivalent phrase — completing a linking verb and describing the subject. Relation acomp for an adjective (oprd after seem or appear). The soup smells wonderful. The road was icy.
See: Articles, Adjectives & Objects
Objective complement: Like a subjective complement, but it names or describes the direct object, not the subject. It follows a backslash that comes after the object and points back to it. They painted the fence white. The judges called the dance a success.
See: Indirect Objects & Complements

Practice on a real sentence

A linking verb with a predicate adjective. In Roles, the Pred. adjective box holds the adjective and the words that belong to it. When you confirm it, the diagram draws a backslash after is, not a half vertical. Inside that box, as that one is a prepositional phrase, not a clause.

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