THE COMPLEMENT OF THE SUBJECT (Cs)
Syntactic and semantic features
The Subject Complement is the obligatory constituent which follows a copular verb and which cannot be made subject in a passive clause:
Who’s there? It’s me/It’s I.
She became a tennis champion at a very early age.
Feel free to ask questions!
The Subject Complement does not represent a new participant, as an Object does, but completes the predicate by adding information about the subject referent. For this reason the Subject Complement differs from the Object in that it can be realized not only by a nominal group but also by an adjectival group (AdjG), as illustrated in the previous examples.
The objective case (me) is now in general use (It’s me) except in the most formal registers, in which the subjective form (it’s I) or (I am he/she) are heard, especially in AmE.
As well as be and seem, a wide range of verbs can be used to link the subject to its Complement; these add meanings of transition (become, get, go, grow, turn) and of perception (sound, smell, look) among others.
The constituent following such verbs will be considered Subject Complement if the verb can be replaced by be and can’t stand alone, without a change of meaning:
I know it sounds stupid, but . . . (= is stupid) cf. *I know it sounds.
That looks nice. (= is nice) cf. *That looks.
More problematic is the constituent following other verbs that could be used intransitively with the same meaning, as in:
Saint Etheldreda was born a Saxon princess. (she was born)
He returned a broken man. (he returned)
He died young. (he died)
We shall consider such constituents as Complements on the strength of the possible
paraphrase containing be (When he returned he was a broken man; When he died he was
young).
There is, typically, number agreement between the subject and its Complement,
and gender agreement with a reflexive pronoun at complement, as in Janet isn’t herself
today. There are, however, several common exceptions to number agreement:
Joan and Lionel make a good couple.
My neighbor’s cats are a nuisance/a joy.
Are these socks wool? No, they’re cotton.
The twins are the same height.
Complements of the type a good couple in Joan and Lionel make a good couple are explicable on semantic grounds, couple being inherently plural in meaning. Semantic criteria may also be invoked to explain the use of a nuisance/a joy in My neighbor’s cats are a nuisance/a joy, since abstractions such as these are equally applicable to singular or plural subjects.
A third type, exemplified by expressions such as wool, cotton, rather an odd color, the same height/length/shape, etc., can all be paraphrased by a PP with of (of wool, of rather an odd color, of the same height, etc.), which formerly had greater currency. They all express qualities of the subject, and in present-day English the NG form without a preposition is the more common.
Copular verbs predict meanings of being something, describing or identifying the subject referent. The identifying type is typically reversible, the attributive is not:
The concert was marvellous. (attributive) *Marvellous was the concert.
The concert was a great success. (attributive) *A great success was the concert.
The orchestra was the London Philharmonic. (The London Philharmonic was the
(identifying) orchestra.)
When be is followed by an expression of location in space or time (in the garden, at 10 o’clock), this Complement is analyzed as locative. Sometimes a circumstantial expression (e.g. out of work) is semantically equivalent to an attributive one (e.g. unemployed).
