The passive was briefly discussed in 1.4. In this chapter and the next various kinds of passives and similar constructions are examined in more detail.

The identification of the passive

1. A simple and obvious type of passive is illustrated by (see 1.4.1):

2. The policemen caught the thief

3. The thief was caught by the policemen

Commonly the Subject of the active sentence is omitted in the passive:

1. The boy was hit

Sentences such as these are referred to as ‘agentless passives’. It is important to note that in English it is not possible simply to omit the Subject of the active sentence to produce:

1. *Caught the thief

If the Agent is not to be mentioned the passive must be used.

If the passive is a typologically valid category, it must, like all such categories, be identified (i) in terms of the meaning or function it shares across languages, and (ii) in terms of its formal marking in individual languages. (For a discussion see Palmer 1986: 2–7.) It can be said that the basic functions of the passive are the promotion of the Patient (or non-Agent) and the demotion or deletion of the Agent (but see 6.7). This does not involve the acceptance of a particular syntactic theory, but merely implies that the functions of the roles of Agent, Patient etc. in the passive can be accounted for in terms of variation from their functions in the active sentence.