In linguistics, control is a construction in which the understood subject of a given predicate is determined by some expression in context.
Control was intensively studied in the government and binding framework in the 1980s, and much of the terminology from that era is still used today.
[1] In the days of Transformational Grammar, control phenomena were discussed in terms of Equi-NP deletion.
Compare the following pairs of sentences: The a-sentences contain auxiliary verbs that do not select the subject argument.
What this means is that the embedded verbs go, do, and lie and cheat are responsible for semantically selecting the subject argument.
[7]The pool was the perfect temperature after being in the hot sun all day.Arbitrary control occurs when the controller is understood to be anybody in general, e.g.[8] The understood subject of the gerunds in these sentence is non-discriminate; any generic person will do.
[9] The null PRO is added to the predicate, where it occupies the position that one would typically associate with an overt subject (if one were present).
In the current context, the trees are intended merely to suggest by way of illustration how control and PRO are conceived of.
In a sense, the controller assigns its index to PRO, which identifies the argument that is understood as the subject of the subordinate predicate.
What is important is that by positing the existence of the null subject PRO, the theoretical analysis of control constructions gains a useful tool that can help uncover important traits of control constructions.
Compare the following a- and b-sentences: The control predicates ask and force semantically select their object arguments, whereas the raising-to-object verbs do not.
[14] Idiomatic expressions retain their meaning in a raising construction, but they lose it when they are arguments of a control verb.
See the examples below featuring the idiom "The cat is out of the bag", which has the meaning that facts that were previously hidden are now revealed.