Sluicing

In syntax, sluicing is a type of ellipsis that occurs in both direct and indirect interrogative clauses. The ellipsis is introduced by a wh-expression, whereby in most cases, everything except the wh-expression is elided from the clause. Sluicing has been studied in detail in recent years and is therefore a relatively well understood type of ellipsis. Sluicing occurs in many languages.

Sluicing is illustrated with the following examples. In each case, an embedded question is understood though only a question word or phrase is pronounced. (The intended interpretations of the question-denoting elliptical clause are given in parentheses; parts of these are anaphoric to the boldface material in the antecedent.)

Sluicing in these examples occurs in indirect questions. It is also frequent in direct questions across speakers, e.g.

The examples of sluicing above have the sluiced material following its antecedent. This material can also precede its antecedent, e.g.

Interrogative phrases in languages with morphological case-marking show the case appropriate to the understood verb (as Ross 1969 and Merchant 2001 document), illustrated here with the German verb "schmeicheln" (to flatter), which governs the dative case on its object.

Languages that forbid preposition-stranding in question formation also forbid it in sluicing (Merchant 2001), as in the following example from German:

In some languages, sluicing can leave behind more than one wh-phrase (multiple remnant sluicing):

Sentences like these are considered acceptable in languages like German, Japanese, Turkish, Russian, and others, although in English, their acceptability seems marginal (but see Bolinger 1978, Merchant 2001, and Richards 2010 for examples). Lasnik 2014 discusses the fact that the wh-phrase remnants in multiple sluicing must be clausemates:

Sluicing has garnered considerable attention because it appears, as Ross 1969 first discussed, to allow wh-fronting to violate the island conditions he discovered:

Ross (1969) is the first examination of sluicing; he argued that sluicing involves regular wh-fronting followed by deletion of the sister constituent of the wh-phrase. This analysis has been expanded in greater detail in Merchant (2001), the most comprehensive treatise on sluicing to date. Such analyses account directly for the case and preposition-stranding facts, but have difficulty accounting for the absence of island effects. A second kind of analysis is represented by Ginzburg and Sag (2000) and Culicover and Jackendoff (2005), both of which present nonstructural analyses of ellipsis, and do not posit unpronounced elliptical material. Such analyses must be supplemented in some way to account for the case facts; nonstructural analyses have not been shown to be able to handle the cross-linguistic distribution of preposition-stranding under sluicing, which appears to track preposition-stranding possibilities in non-elliptical questions. Yet another account of sluicing builds on the catena unit; the elided material is a catena.

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