Wh-movement

In linguistics, wh-movement (also known as wh-fronting, wh-extraction, or wh-raising) is the formation of syntactic dependencies involving interrogative words.

This dependency has been used as a diagnostic tool in syntactic studies as it can be observed to interact with other grammatical constraints.

The term wh-movement stemmed from early generative grammar in the 1960s and 1970s and was a reference to the theory of transformational grammar, in which the interrogative expression always appears in its canonical position in the deep structure of a sentence but can move leftward from that position to the front of the sentence/clause in the surface structure.

[2] Although other theories of syntax do not use the mechanism of movement in the transformative sense, the term wh-movement (or equivalent terms, such as wh-fronting, wh-extraction, or wh-raising) is widely used to denote the phenomenon, even in theories that do not model long-distance dependencies as a movement.

These examples illustrate that wh-movement occurs when a constituent is questioned that appears to the right of the finite verb in the corresponding declarative sentence.

[4] The basic examples above demonstrate wh-movement in main clauses in order to form a direct question.

Many instances of wh-fronting involve pied-piping, where the word that is moved pulls an entire encompassing phrase to the front of the clause with it.

[9] In some cases of wh-fronting, pied-piping is obligatory, and the entire encompassing phrase must be fronted for the sentence to be grammatically correct.

When the wh-word appears underneath a blocking category or in an island, the entire encompassing phrase must be fronted.

A syntactic island is a construction from which extracting an element leads to an ungrammatical or marginal sentence.

Wh-islands are weaker than adjunct islands, and violating them results in a sentence that at minimum sounds ungrammatical to a native speaker.

The relevant constraint is known as the complex NP constraint,[23] and comes in two varieties, the first banning extraction from the clausal complement of a noun, and the second banning extraction from a relative clause modifying a noun: Sentential complement to a noun: Relative clause: Extraction out of object that-clauses serving as complements to verbs may show island-like behavior if the matrix verb is a nonbridge verb (Erteschik-Shir 1973).

The wh-movement is motivated by a Question Feature/EPP at C (Complementizer), which promotes movement of a wh-word from the canonical base position to Spec-C.

This movement could be considered as "Copy + Paste + Delete" movement as we are copying the interrogative word from the bottom, pasting it to Spec-C, and then deleting it from the bottom so that it solely remains at the top (now taking the position of Spec-C).

Ex-situ trees allow the movement to Spec-C, while in-situ do not as the head C lacks the EPP feature.

In the following English example, a strikeout-line and trace-movement coindexation symbols—[Whoi ... who ti ...]—are used to indicate the underlying raising-movement of the closest wh-phrase.

This movement produces an overt sentence word order with one fronted wh-question: e.g.: [Whoi did you help who ti make what?]

'The following examples illustrate wh-movement of an object in French: IlstheyonthavevuseenPierre.PeterIls ont vu Pierre.they have seen Peter'They saw Peter.

'QuiWhoest-ce qu'is it thatilstheyonthavevu?seenQui {est-ce qu'} ils ont vu?Who {is it that} they have seen'Who did they see?

[25] For example, see the following German phrases: IchIweißknownicht,not,werwhowaswhatgesehenseenhathasIch weiß nicht, wer was gesehen hatI know not, who what seen has"I do not know who saw what"IchIweißknownicht,not,waswhatwerwhogesehenseenhathasIch weiß nicht, was wer gesehen hatI know not, what who seen has"I do not know what who has seen"In a., the gloss shows that the wh-phrase [what] has "crossed over" wh-phrase [who] and is now in Spec-CP to satisfy the [+Q Wh] feature.

The following example illustrates multiple wh-movement in Mandarin: 你nǐYou想xiǎngwant知道zhīdǎoknow瑪麗MǎlìMary為什麼wèishénmewhy買了mǎilebuy-PAST什麼shénmewhat你 想 知道 瑪麗 為什麼 買了 什麼nǐ xiǎng zhīdǎo Mǎlì wèishénme mǎile shénmeYou want know Mary why buy-PAST what'What do you wonder why Mary bought it?

[28] The following example can translate into two meanings: 你nǐYou想xiǎngwant知道zhīdǎoknow誰shéiwho買了mǎilebuy-PAST什麼shénmewhat你 想 知道 誰 買了 什麼nǐ xiǎng zhīdǎo shéi mǎile shénmeYou want know who buy-PAST what'What is the thing x such that you wonder who bought x?'

[30] This can be seen in the following example, where the word for "what" stays in-situ since it is c-commanded by the phrase in Mandarin meaning "at where": 你nǐYou想xiǎngwant知道zhīdǎoknow瑪麗MǎlìMary在zàiat哪裡nǎlǐwhere買了mǎilebuy-PAST什麼shénmewhat你 想 知道 瑪麗 在 哪裡 買了 什麼nǐ xiǎng zhīdǎo Mǎlì zài nǎlǐ mǎile shénmeYou want know Mary at where buy-PAST what'What is the thing x such that you wonder where Mary bought x?'

[31] The phrase structure for wh-words in Bulgarian would look like is shown in Figure 1 below, where a wh-cluster is formed under [Spec-CP].

KojWhokakhowkogowhomeiscelunal?kissedKoj kak kogo e celunal?Who how whom is kissedWho kissed whom how?In Bulgarian, we see in Example #4 that to defer from forming a sequence of the same wh-words, a wh-element is allowed to remain in-situ as a last resort (Bošković, 2002).

Here, the choice of using one form of question over the other is optional; either sentence can be used to ask about the two particular DP constituents expressed by two wh-words.

[25] For echo questions in English, it is typical for speakers to emphasize the wh-words prosodically by using rising intonation (e.g.,You sent WHAT to WHO?).

For example, topic questions in Chinese have the same sentence structure as their answers: 你nǐyou在zàiPROG做zuòdo什麼？shénmewhat[你在做什么？]  你 在 做 什麼？nǐ zài zuò shénmeyou PROG do whatWhat are you doing?The response to which could be: 我wǒI在zàiPROG編輯biānjíedit維基百科。Wéi jī bǎi kēWikipedia[你在做编辑维基百科。]  我 在 編輯 維基百科。wǒ zài biānjí {Wéi jī bǎi kē}I PROG edit WikipediaI am editing Wikipedia.Chinese has a wh-particle, no wh-movement.

In this regard, theories of syntax tend to explain discontinuities in one of two ways, either via movement or via feature passing.

Theories that posit movement have a long and established tradition that reaches back to early Generative Grammar (1960s and 1970s).