§2,4 Lexical restrictions 243Things are different in [ii], however. Suppose the context is one where I've just
said that I've been shopping: a tie is new, while I (or me) is old information. Here
only the active version will normally be acceptable.Active is the default in the voice system. The use of actives is not restricted by
actual constraints relating to the combination of old and new information, but the
passive is. This is the generalisation that holds:
[1 1] In a passive clause it is not normally possible for the subject to be new when
the internalised complement is old.There is far more to the choice between active and passive clauses than there is
space to discuss here. But all we want to point out is that while they normally have
the same core meaning, they are NOT FREELY INTERCHANGEABLE. They differ in
how the information is presented, and one important factor in the choice between
them concerns the status of the two major NPs as representing old or new
information.
2.3 Short passives
In almost all cases the internalised complement is OPTIONAL. The
passive clauses with no internalised complement are called short passives; the ones
discussed so far are called long passives. Short passives are actually much more fre
quent than long passives. They have an important function: they enable us to LEAVE
OUT something that would be obligatory in the active, namely a main clause subject.
In [12] the active versions are not grammatical, but the passive ones are fine:
[12] ACTIVE VOICE
a. *Built the house in 1960.
ii a. *Damaged your car.
III a. * Know little about the cause of ALS.
iv a. *Made mistakes.PASSIVE VOICE
b. The house was built in 1960.
b. Yo ur car was damaged.
b. Little is known about the cause of ALS.
b. Mistakes were made.The passive versions enable us to avoid saying anything about
who built the house (we may have no idea who it was, or it may not be relevant);
which employee of ours accidentally damaged your car (there are liability
issues !);
who exactly is ignorant (nobody knows the cause of amyotrophic lateral sclero
sis); or
who blundered (people don't always want to directly admit error).2.4 Lexical restrictions
Most transitive active clauses have passive counterparts, but not all. Some
exceptional verbs are (either generally or in certain uses) inadmissible in passives: