In some particular cases, the reference of null arguments in LIS may be ambiguous. One of such cases is verb phrase ellipsis (SYNTAX 2.5). In the example below, the second clause lacks the predicate and the object. The reference of the omitted object (i.e. the car washed by Paolo) is ambiguous as it may refer either to Pietro’s car or to Paolo’s car.
pietroa car poss3a water CL(closed G): ‘wash_car’ ixb paolo identical
‘Pietro washed his car, Paolo did too.’
The ambiguous interpretation of the null object can be resolved through the context.