To sum up, the concept of the theta theory answered several question remained unanswered in earlier grammars. The notion of θ-criterion provides us a base to generate well formed sentences. The number of underlying theta role is the same in all languages but as languages differ in regard to their capacity of theta absorption, the surface manifestation of NPs with theta role may differ from language to language. Thus the theta theory/theta criterion accounts for all types of verbs and their possible arguments more adequately than the traditional division of verbs into intransitive and transitive does. Theta absorption states that an argument may not be in the surface structure of a sentence and still it is grammatical. It suggests that the omitted argument has been θ-absorbed. Such θ-absorbed argument can be recovered by analyzing the predicate itself.
INTRODUCTION TO LINGUISTICS & PHONETICS - PREDICATE AND ARGUMENT STRUCTURES