In linguistics, inverse copular constructions, named after Moro (1997), are a type of inversion in English where canonical SCP word order (subject-copula-predicative expression, e.g. Fred is the plumber) is reversed in a sense, so that one appears to have the order PCS instead (predicative expression-copula-subject, e.g.
Inverse copular constructions are intriguing because they render the distinction between subject and predicative expression difficult to maintain.
The confusion has led to focused study of these constructions,[1] and their impact on the theory of grammar may be great since they appear to challenge the initial binary division of the sentence (S) into a subject noun phrase (NP) and a predicate verb phrase (VP) (S → NP VP), this division being at the core of all phrase structure grammars (as opposed to dependency grammars, which do not acknowledge the binary division).
In the inverse copular constructions, the copula agrees with the singular predicative expression to its left as opposed to with the plural subject to its right.
In fact, copular sentences that maintain the canonical groupings are not adequate on empirical grounds, since a very unorthodox left-branching structure is necessary, or if one rejects the canonical groupings and positions the subject inside a VP-like constituent, then one has to assume that the subject NP and copula verb can form a type of VP to the exclusion of the predicative expression.