§2.2 Traditional errors in defining the subject^69The subject NP commonly (but by no means invariably) identifies a topic for the
clause, i.e. what the clause is primarily about, and the predicate makes some sort
of comment about that topic. For example, Paris is lovely in the spring has Paris
as the subject, and it is likely to be interpreted as saying something about Paris;
Spring is a great time to visit Paris has spring as the subject, and it is likely to be
interpreted as saying something about spring.Many definitions of the subject given in grammars and dictionaries represent a mas
sive overgeneralisation of the first point: the subject is simply defined as the performer
of the action expressed in the verb. Less commonly, it is defined as the topic of the
sentence, the part that identifies what the sentence is about - a similarly massive over
generalisation of the second point. There is something in both of these that is relevant
to a definition of the subject at the general level: many languages have a function in
the clause that is often associated with the semantic role of actor or with the topic and
that shows other signs of primary syntactic importance in the clause (though some
languages seem to be organised rather differently). But the correlation in English
between subject and actor or topic is far too complex for the above definitions to work
at the language-particular level. Let us examine the two definitions in turn.
(a) Subject and actor
The old-fashioned definition of the subject as the performer of the action expressed
in the verb works well enough with a sentence like We wandered down the street;
but it fails completely with examples like those in [11]:
[^11 ] i She knows him well.
ii Ernie suffe red a heart attack.
iii My mother was attacked by the neighbour's dog.
She is the subject of [i], but knowing isn't an action. Notice that [i] can't be used
in answer to a do question (such as What does she do ?), so nothing in [i] talks
about anyone performing an action. If we took the old-fashioned definition seri
ously we would have to say that there is no subject here. But she has all four of
the syntactic properties that are the relevant ones for English: it's before the verb,
it's in nominative case, the verb agrees with it, and it follows the auxiliary in the
corresponding interrogative (Does she know him well?).
In [ii] we do have a description of an event (rather than a state, as in [iD, but that
still doesn't mean there is a performer of an action. Suffering isn't an action that
Ernie performed on the heart attack. Again, then, the referent of the syntactic
subject doesn't have the semantic role of actor.
Example [iii] does describe an action, but it's a passive clause (the corresponding
active clause would be The neighbour's dog attacked my mother), and the actor
role is associated not with the subject, my mother, but with the complement of the
preposition by, namely the NP the neighbour's dog.
So the subject of an English clause certainly cannot be identified on the basis of
semantic role: it can be associated with a range of roles, depending on the kind of
situation described and whether the clause is active or passive.