• The following sections of A Comprehensive Grammar of The English Language (Randolph Quirk, Sidney Greenbaum, Geoffrey Leech, Jan Svartik, Longman, London & New York, 1985) were consulted in preparing this entry:
The active-passive correspondence
The passive auxiliaries be and get
The passive gradient
1. the alternative passive auxiliary, get: It is often possible to use the verb get as an auxiliary in forming the passive (even though it does not act in this way in other contexts.) There are restrictions however: first, get is not normally used if an animate (i.e. living) agent is mentioned in a by- phrase. For example, Jill got hit by a car but, Jill was hit by Harry; secondly, get is avoided in formal contexts (and is much less common than be even in informal contexts.) (It is important not to be misled by the fact that get can be used as a passive auxiliary into the error of regarding as passive sentences such as, Sara is getting tired of Harry’s behavior; here, get is being used as a “resulting copula” with a meaning similar to become.)
2. the passive gradient: A sentence like, Tom is interested in chess, is regarded as a “semi-passive” by the authors of CGEL. Semi-passives belong to a class “whose members have both verbal and adjectival properties” (§3.76, 168). As they point out, such sentences do have “active analogues” (Chess interested Tom) but the past participles that occur with them also have adjectival properties (e.g allowing modification with more and allowing replacement with copular as in, Tom seemed interested in chess.) Finally, further along the “gradient” (§3.77) are “pseudo-passives” like Modern society is getting incredibly complicated, for which no “active transform”is possible.
3. active-passive pairs with dissimilar truth values: Generally speaking, an active clause has exactly the same meaning as its passive counterpart. It’s merely a matter of looking at the same fact in two different ways. There are exceptions however: as the authors of CGEL point out, the sentence, Every schoolboy knows at least one joke does not have the same meaning as At least one joke is known by every schoolboy. They also point out that the switch from active to passive can change the meaning of a modal auxiliary and give as an example the pair, John cannot do it and It cannot be done by John.