Definite null instantiation is the absence of a frame element that is recoverable from the context. It is similar to a zero anaphor.
Indefinite null instantiation is the absence of the object of a potentially transitive verb such as eat or drink.
Constructional null instantiation is the absence of a frame element due to a syntactic construction, e.g. the optional omission of agents in passive sentences.
Ruppenhofer and Michaelis 2014 ↩