There are good reasons for assuming that relative elements are like wh -phrases in that they are moved into the position preceding the complementizer. This cannot be shown for Standard Dutch, however, because the phonetic content of the complementizer is obligatorily elided in relative clauses, as is indicated in (269a) by strikethrough. It is nevertheless quite plausible, as many Flemish and Frisian dialects do allow the complementizer to be overtly expressed; see Pauwels (1958), Dekkers (1999:ch.3), Barbiers et al. (2005:section 1.3.1), Boef (2013:ch.3), and the references cited there. Example (269b) shows that movement of the relative element is obligatory; leaving it in situ results in ungrammaticality.

The obligatoriness of movement can again be motivated semantically by assuming that wh -movement of the relative element creates an open proposition (that is, a one-place predicate) which can be used to modify the head noun. On this view, a relative clause is semantically similar to an attributive modifier like boze in de boze man 'the angry man' , which is likewise a one-place predicate. This more or less classical idea is attractive, of course, given that it suggests that the role of wh -movement in question formation and relativization can be unified. Although there is currently a debate going on about the question as to whether the derivation of relative clauses given in (269) is fully correct, we will simply assume that the suggested semantic motivation for wh -movement in relative clauses is on the right track and that any syntactic account of relativization should be able to accommodate it in order to be tenable; we refer to Bianchi (1999), De Vries (2002:ch.4) and Salzmann (2006:ch.1) for extensive reviews of the debate mentioned above.

If wh -movement in relative clauses is indeed motivated by the need to create an open proposition, we would again expect that it is precisely the relative element that must be moved into clause-initial position. This raises the question as to whether wh -movement will trigger pied piping if syntactic constraints prohibit extraction. The examples in (270) show that this is indeed the case: as wh -movement of the italicized relative element would suffice to create the wanted open predicate, pied piping of the larger phrase should be motivated by appealing to a syntactic restriction that prohibits extraction of the relative element from the noun phrase wiens vader 'whose father' .

The restrictions on extraction of relative elements are more or less the same as those on extraction on wh -elements. In order to avoid a full repetition of the discussion on stranding and pied piping in Section 11.3.1.1, we will illustrate this for PPs only. The examples in (271) first show that prepositional objects like naar wie 'at who' require pied piping. However, if the PP has the pronominalized form waarnaar (which is easier to get for human entities in relative clauses than in wh -questions as the result of the presence of an antecedent with the feature +human) stranding is possible and may even be preferred (although we do not have frequency data available to corroborate this).

The examples in (272) show the same thing for prepositional complementives; see P4.2.1.1 for extensive discussion of the fact that verbs of location like zitten 'to sit' take a complementive. If the complement of the preposition is the interrogative pronoun wie , pied piping is obligatory, whereas stranding seems to be the preferred option in the case of pronominal PPs.

Postpositional complementives differ from prepositional ones in that they do not allow pied piping but require stranding of the postposition. We illustrate this in (273) by means of the complementive de boom in 'into the tree' .

The examples in (274), finally show that circumpositional complementives such as tussen wie door must be split: the first member of the circumposition plus the wh -phrase tussen wie is preposed while the second member door stays in situ.

The judgments on the examples above show that, as in questions, pied piping and stranding are more or less in complementary distribution; the formation of wh -questions and relativization seem in fact to exhibit essentially the same pattern. This suggests that we will be able to account for the examples in (271)- (274) by adopting the set of assumptions from Section 11.3.1.1, sub VI, including the "avoid pied piping" constraint; We refer the reader to this subsection for the general line of reasoning, which can be straightforwardly applied to the examples in (271) to (274).

Relativization is compatible with long wh -movement: we illustrate this in example (275) for a direct object and an adverbial phrase extracted from an object clause.

As in the case of wh -question formation, long wh -movement is only possible from argument clauses; the examples in (276) show that adjunct clauses prohibit extraction of both arguments and adjuncts and should therefore be considered strong islands for wh -movement of relative elements.

Long wh -movement requires that the matrix clause contains a so-called bridge verb. Example (277b) shows for wh -questions that while long wh -movement is fully acceptable with the verb zeggen 'to say' , it is not easily possible with verbs of saying that express a manner component like schreeuwen 'to yell' . Example (277c) shows that we find the same contrast with long wh -movement in relative clauses.

It seems, however, that the set of bridge verbs is not identical for the two constructions. While Section 11.3.1.2 has shown that object clauses selected by factive verbs like weten 'to know' are weak islands for long wh -movement in wh -questions, this does not seem to hold for long wh -movement in relative clauses. A corpus of long wh -movement constructions manually collected by Jack Hoeksema in fact shows that weten is the most frequent bridge verb in relative clauses derived by long wh -movement; cf. Table 5.2 in Schippers (2012). Although Schippers does not give concrete examples that illustrate the bridge function of weten , a Google search (7/27/2014) on the search string [ die ik wist dat ] shows that this construction is indeed relatively frequent; the examples in (278) provide two attested examples. Observe that example (278a) seems to show that long wh -movement of subject pronouns does not give rise to the complementizer-trace effect in relative clauses for at least some speakers; see also Van der Auwera (1984), Boef (2013:35), and Coppen (2013).

It should be noted, however, that speakers seem to differ in their appreciation of relative clauses with long wh -movement. Salzmann (2006:153), for example, notes that some speakers prefer resumptive prolepsis constructions like (279) to long wh -movement constructions like (278).

The island-sensitivity of wh -questions and relative clauses does not differ when it comes to strong islands. We will illustrate this here for embedded questions only. Example (280a) involves an embedded polar yes/no question and (280b) shows that such clauses block long wh -movement of relative elements; the competing resumptive prolepsis construction in (280c) does give rise to an acceptable result. The examples in (281) show the same by means of an embedded wh -question.

This subsection briefly discusses wh-movement in so-called cleft and pseudo-cleft constructions. The cleft construction illustrated in (282a) is characterized by the fact that it involves the subject pronoun het 'it' , a contrastively focused complementive (here: je vriend ) and a clause that closely resembles a relative clause. However, the clause does not function as a modifier of the complementive, as is clear from the fact that it neither restricts the denotation of the head noun vriend 'friend' nor provides additional information about the referent of the definite noun phrase je vriend 'your friend' . Instead, examples like (282a) express identity statements: the person who stole the book is identified as your friend. That we are not dealing with a modifier of the complementive is also clear from the fact that the clause cannot occur adjacent to it if there is a verb in clause-final position; restrictive and non-restrictive relative clauses are normally possible in preverbal position. The number sign indicates that examples like (282b) cannot be interpreted as an identity statement, although it can be used to refer to a certain friend who also happens to be a thief.

In the linguistic literature on Dutch, cleft constructions have received little attention, which may be related to the fact that some researchers consider it a barbarism, which replaces the more regular construction that uses accent only, as in Je vriendje heeft het boek gestolen'Your friend has stolen the book'; see Paardekooper (1986:901), who seems to think that French influence plays a role here. Paardekooper analyzes the clause as an extraposed subject introduced by the anticipatory pronoun het . The reason is that it can also be preposed, as in (283a), which results in a construction that closely resembles the English pseudo-cleft construction. The fact that (283a) is more or less equivalent to (283b) further suggests that the clause is a free relative, and this is indeed what is suggested by Paardekooper as well as Smits (1989:section 4.2).

De Vries (2002) voices some scepticism about claims that constructions of the type above should be identified with English cleft and pseudo-cleft constructions because the Dutch constructions have hardly been studied in their own right so far and it is not clear whether the findings for English carry over to Dutch. Since a detailed discussion will have to await until future research has clarified this issue, we confine ourselves here to noting that the movement of the relative-like element die into clause-initial position exhibits the hallmarks of wh -movement: the examples in (284), for instance, show that it is not clause-bound but nevertheless island-sensitive in that it cannot be extracted from an embedded question or an adjunct clause.