Exceptional case-marking

In linguistics, the term exceptional case-marking (ECM) denotes a phenomenon where the subject of an embedded infinitival verb seems to appear in the superordinate clause and, if it is a pronoun, is unexpectedly marked with object case morphology (him not he, her not she, etc.). The unexpected object case morphology is deemed "exceptional". The term ECM itself was coined in the Government and Binding grammar framework, although the phenomenon is closely related to the accusativus cum infinitivo constructions of Latin. ECM-constructions are also studied within the context of raising. The verbs that license ECM are known as raising-to-object verbs. Many languages lack ECM-predicates, and even in English, the number of ECM-verbs is small. The structural analysis of ECM-constructions varies in part according to whether one pursues a relatively flat structure or a more layered one.

The ECM-construction is licensed by a relatively small number of verbs in English (e.g., believe, judge, prove, want, etc.):

The strings in bold are the ECM-constructions. The pronouns are marked with object case morphology, but they function semantically as the subjects of the infinitival verbs to their right, i.e., they acquire their theta roles from the verb to their right. Many ECM-verbs allow the same meaning to be expressed with a full object clause (a finite clause), e.g.:

Since the meaning across these clauses remains consistent, one tendency has been to view the ECM-material (i.e., the material in bold in the first four examples) as a type of small clause that is analogous to the full clausal counterpart. On this approach, the object forms a constituent with the infinitive to its right. The primary trait of the ECM-object/subject is that it is NOT a semantic argument of the matrix predicate, which means that it is not semantically selected by the matrix verb. In this area, ECM-constructions should not be confused with control constructions, since control predicates semantically select their object (e.g., They told us to start).

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