Nominal predicate complements are more likely than adjectival and participial predicate complements not to agree in case with the noun phrase (NP) of which they are complements and instead to occur in a non-agreement case (such as, in Lithuanian, the instrumental).
Standardized
IF adjectival and participial predicate complements do not agree in case with the NP of which they are complements, THEN nominal predicates will not agree in case either.
or, avoiding double negation:IF nominal predicate complements agree in case with the NP of which they are complements, THEN adjectival and participial complements will also agree in case.
or, avoiding double negation:IF nominal predicate complements agree in case with the NP of which they are complements, THEN adjectival and participial complements will also agree in case.