Introducing English Linguistics

clause
functions
: subject, predicator, object (direct or indirect), complement
(subject or object), and adverbial. In the above example, The child functions
as subject, rode as predicator, and a bike as direct object. Similar forms can
have different functions because the function that a particular form has
is relative to other forms with which it occurs. In the sentence The police
officer questioned the child,  the child now has the function of direct object,
not subject of the sentence.
Of all the clause functions, the predicator is most important, since the
lexical verb within the predicator determines the argument structure of a
clause: the number and type of