Pied-piping in Word Grammar*

RICHARD HUDSON (13.5pt)

Abstract

Pied-piping, as in the book in which I found it, is a serious challenge for any theory of syntax because the preposition (in) takes its position from its complement (which) rather than, as expected, from the word on which it depends (found). Theories based on phrase structure, whether transformational or not, explain this by allowing the wh-feature of which to ‘percolate’ up to the whole PP in which, but cannot explain the absence of the ‘wh-prepositions’ that we might expect to develop diachronically, nor the non-wh semantics of the supposed wh-PP. Word Grammar (WG) offers a completely different alternative which focuses directly on the one exceptional characteristic of pied-piping: word order. Since 2007, WG has treated word order in terms of the ‘landmark’ relation, which is separate from dependency structure; this allows the default rules for deriving landmarks from dependencies to have exceptions. One such exception is that the pied-piped preposition simply has no landmark at all. This account explains the peculiarities of pied-piping as a purely surface matter of word order without implications for classification or semantics.

1 Introduction

This paper is about the analysis of sentences like (1).(1) This is the book in which I found it.

The challenge is to explain why in stands before which rather than in its expected place after found it, as in (2) and (3).

(2) This is the book which I found it in.(3) I found it in this book.

The problem is that the rules for front-shifting wh-pronouns such as which do not, in themselves, allow the front-shifting of prepositions. As we all know, the only reason why in stands at the start of the relative clause in which I found it is that it

*Thanks to Professor Kensei Sugayama for the energetic and effective way in which he has supported and promoted Word Grammar over the years.

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has been ‘pied-piped’1 into this position by which; the preposition itself has no grammatical reason to be there.

Moreover, this is a very exceptional case of a head word taking its position from its dependent, a reversal of the usual pattern which moves the problem out of mere descriptive linguistics onto the plane of general linguistic theory. But notice that the only issue, from a theoretical point of view, is the order of words (and in particular, the position of in). Nothing else is exceptional in (1) – in fact, apart from the position of in, (1) has exactly the same syntactic structure as (2), paired with exactly the same semantics and morphology.

Another challenge is the difference between interrogative and relative clauses. Interrogative wh-pronouns allow a different range of pied-piping patterns from what relative wh-pronouns do (Huddleston and Pullum 2002:910, 1040). Huddleston and Pullum (who use the term ‘upward percolation’ rather than pied-piping) give the following examples. I have italicized the phrase whose position is affected by this percolation.

(4) In which drawer do you keep the bank statements?(5) *The president of which country was she?(6) What size shoes do you take?(7) How big a hole did it make?

These interrogative examples show that (in Huddleston and Pullum’s terminology) the wh-feature can percolate up from the interrogative pronoun to a preposition (4), but no further (5); and that it can also percolate up to a pre-modified noun (6) or through an adjective to the determiner a (7).

This pattern is quite different from the one found with the relative pronouns in the next examples:

(8) the curtain behind which Kim was hiding(9) She’s just sat her final exam, the result of which we expect next week.(10) They will be involved in several projects, one of the most important of

which will be to find ways to use the new superconductor in chips that can provide the brains of a new generation of supercomputers.

(11) The many varieties of mammalian skin secretions perform a wide range of functions, prominent among which is sexual attraction.

(12) I became disturbed by a ‘higher criticism’ of the Bible, to refute which I felt the need of a better knowledge of Hebrew and archaeology.

(13) They take a rigorous examination, passing which confers on the student a virtual guarantee of a place at the university.

These examples show that (as in interrogative clauses) the relative pronoun’s influence can percolate up to a preposition (8). This is the only possibility in a

1 The term ‘pied-piping’ was introduced by Ross (Ross 1967), alluding to the fairy-tale in which the ‘Pied Piper’ (dressed ‘cap à pied’ in colourful clothes) led all the children of the German town of Hamlin to their death.

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restrictive relative clause, but in non-restrictive relatives there are many other possibilities: percolation up through a preposition and noun to a determiner (9), through a chain of six prepositions, nouns and determiners (10), through a preposition to an adjective (11), through a verb to the infinitival to (12), or to a gerund (13). This freedom is further illustrated by the invented examples used by Ross to illustrate the process of pied-piping, (14):

(14) reports, the height of the lettering on the covers of which the government prescribes

As an aside on Word Grammar (WG), it is worth pointing out the consequence of taking determiners as heads (as in these books, where books depends on these rather than the other way round). This analysis means that Huddleston and Pullum’s examples such as Which car did she take? do not involve percolation because the head of which car is which. Similarly, in what size shoes it is what, rather than size, that depends directly on shoes, which produces a shorter percolation path than Huddleston and Pullum envisage. Nevertheless, most of their examples are as challenging for WG as for any other theory.

The discussion so far has established two facts about pied-piping (or upward percolation):

It is theoretically exceptional in allowing a phrase’s position to be determined by a word other than its head.

The details of the phrases influenced in this way by a wh-word vary according to whether the wh-word is an interrogative or a relative, and whether the relative clause is restrictive or non-restrictive.

In short, the solution must combine general theory with descriptive flexibility.Given that pied-piping really is exceptional, any theory of syntax needs a sub-

theory which explains exactly how this exceptionality can be accommodated in the general theory. All the major theories offer some kind of account of pied-piping (Falk 2006), but because of other differences between the theories they are hard to compare and evaluate. As just one example of an established analysis, consider the one offered by Head-driven Phrase Structure Grammar (Pollard and Sag 1994), which exploits the very rich and flexible feature structures which are part of that tradition and which allow features of daughters to percolate up to the mother node. Feature-percolation is a fundamental and general property of phrases, but normally the percolated features are those of the phrase’s head; in WG terms, the phrase and its head word are identical (which is one of the reasons why I argue that the phrase is redundant). However, pied-piping is exceptional in allowing percolation of features of a non-head wh-pronoun; for instance the phrase behind which in (8) has not only the regularly percolated features of behind (which make it a PP), but also the wh-feature of which.

The weakness of this analysis is that the only evidence that in which has the wh-feature is its position. Neither the phrase as a whole, nor its head, has any of the

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expected morphology or semantics of a wh-word which might give a form such as *whehind which or a meaning such as ‘x such that x is a position behind y’ (where ‘y’ is the referent of which). To pursue the semantic point, if behind which had wh-type semantics in the curtain behind which Kim was hiding, then behind which would refer to the curtain, but in fact it refers to a place behind the curtain. In short, the wh-feature on behind which has different consequences from the one on which, so it cannot be the same feature and percolation is the wrong machinery. Whatever alternative machinery is needed must separate the consequences for word order from all the other consequences of the wh-feature.

The purpose of this paper is to propose a WG analysis of pied-piping which does separate word order from other characteristics. The next section introduces the parts of WG theory that are relevant to this analysis, which section 3 applies to the English facts sketched above.

2 Word order in WGThe explanation for word order in WG, as in every other theory, builds on the abstract dependencies that hold words together. These dependencies are, of course, relations, but in WG relations are concepts (‘relational concepts’) which, like entity concepts, exist in order to bring together a bundle of properties. To take an entity example, the concept ‘bird’ combines properties which correlate strongly as properties of the same entity, such as having two legs, flying and having a beak; and similarly, a relational concept such as ‘on’ combines properties such as ‘aboveness’ and ‘support’. In the domain of syntax, dependencies are the means for bringing together diverse relations such as syntactic valency, semantic valency, morphological selection, agreement and (of course) word order. The classic case is the dependency ‘subject’, which typically combines a dozen or more characteristics (Keenan 1976).

In this view of concepts, each concept, including relational concepts, may be defined by its relations to other concepts; but it is separate from these other defining concepts. For example, take the concepts associated with a typical Western cooked meal: starter, main course and dessert. Each of the courses is an entity with various properties determining the amount and kind of food that it consists of, but one of their properties is their sequential ordering, with the starter before the main course and the dessert after it. Sequential ordering is a relation, and must be represented mentally as a relation link even though our linear writing allows us to show it on the page as a left-right sequence; so in the case of a meal we must recognise two relations between the main course and the starter: the ‘starter’ relation, which recognises that this starter ‘belongs’ to this main course, and the ‘before’ relation (a subdivision of Langacker’s ‘landmark’ relation - Langacker 2007, Hudson 2007). This typical arrangement is shown in Figure 1, where the oval shapes distinguish relational concepts from entities, and the

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landmark relations are shown above the entities (a new notational convention for WG, but one which I shall exploit when we return to syntax). When applied to a particular meal, we can predict that the main course’s starter will be before it, and its dessert will follow it. However, thanks to default inheritance, exceptions are allowed, so we can imagine a meal where the starter is accidentally delayed, so the eaters decide to leave it till after the main course; in that case, its other properties will justify classifying it as a starter, but it will have an exceptional sequential order. In short, landmark relations are separate from other ‘dependencies’ (illustrated here by the ‘starter’ and ‘dessert’ relations).

Figure 1: Sequential order in a meal

Word order is a particular case of the same sequential order that we find in meals, and uses the same landmark relations. The ‘before’ relation of cows to moo is an example of just the same relation as we find between starters and main courses. When applied to dependencies and word order, the principle of separating order from other relations means that a dependency such as ‘subject’ between a verb and its subject is separate from the order of these two words; for instance, in Cows moo we can recognise not one but two syntactic relations between cows and moo: a subject relation and a ‘before’ relation. The grammar of English allows the latter to be predicted from the former, but the two relations are nevertheless distinct. The analysis is shown in Figure 2, which uses the same notation as in Figure 1, with the addition of a vertical arrow which conventionally picks out the root word, which has no landmark.

Figure 2: Dependency and landmark relations combined in Cows moo.

starter main course dessert

starter dessert

afterbefore

Cows moo

subject

before

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Dependencies are highly relevant to landmark relations, because any word-order rules that the grammar may contain will start from dependencies; for instance, the English rules which allow Cows moo but not *Moo cows require the verb’s subject to be before it, with a range of exceptional cases such as Do cows moo? and Here comes John, where the subject is after the verb. By default, a word’s dependents all take that word as their landmark; indeed, one of the reasons why dependencies are fundamentally asymmetrical is that the dependent takes its position from the parent (the word on which it depends), and not the other way round. This fundamental principle is what is at stake in pied-piping, where a dependent wh-word determines the position of its parent; so in which takes the position required by which rather than by its head in.

Another fundamental principle of word order requires what we might call ‘phrasal integrity’: each of the phrases defined by dependency structure should be uninterrupted – i.e. it should form a continuous chain of words which does not contain any other words. Just as in phrase-structure analysis, a word’s phrase consists of that word plus the phrases of any dependents that it may have. For instance, in I like red wine, the phrase defined by wine consists of red wine, and in this sentence the phrase has integrity because it is not interrupted by words from any other phrase. But in *I red like wine, the phrase has lost its integrity because red and wine are separated by like, which is not part of that phrase. However intuitively obvious this principle may be, it is surprisingly hard to formulate in terms of dependencies, and especially so when rich dependency structures are allowed as in WG. In simpler versions of dependency grammar it is expressed as the requirement that structures should be ‘projective’ (Robinson 1970), in the sense that dependency lines should not cross (as they would in any analysis of *I red like wine). WG has seen a series of slightly different analyses, variously called ‘adjacency’ (Hudson 1984:98, Hudson 1990:117), ‘the no-tangling principle’ (Hudson 1998:20), ‘landmark transitivity’ (Hudson 2007:139) and ‘the best landmark principle’ (Hudson 2010:171). Leaving aside these important theoretical details, the principle means that words which share the same landmark stick together even in languages with ‘free word order’. And, of course, in languages like English the before/after direction is determined by the dependencies concerned.

However, not every word has a landmark; most obviously, a non-dependent word such as moo has none, but this is as expected if landmarks follow from dependencies: no dependency, no landmark. But in principle, the separation of landmarks from dependencies allows exceptional dependencies to exist without landmarks. This possibility will provide the basis for the WG explanation for pied-piping which I develop in the rest of this paper.

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3 Wh-words and extraction

Pied-piping is always triggered by wh-words, so we start by considering the special properties of wh-words. As we have already seen, pied piping has very different constraints in interrogative, restrictive relative and non-restrictive relative clauses, so eventually we shall have to distinguish the wh-words found in these clauses, but they all share the following special characteristics.

Syntactically, they are special because of their valency requirements, which allow them to face in two directions at the same time. Like typical pronouns, they can be used as dependents of other words, seen most simply in elliptical examples like (15).

(15) (Someone has borrowed it, but) I don’t know who.This allows them to be part of a ‘higher’ clause, but they are also part of the ‘lower’ clause (the relative or interrogative one) which follows them. This clause is rooted in the verb which is the wh-word’s complement. Although this verb is optional for interrogative pronouns (as in (15)), it is obligatory for relative pronouns, even when it could be guessed from the context.

(16) Someone has borrowed it, but I can’t identify the person who *(borrowed it).

The possibility of a complement verb is shared with many other kinds of subordinate clauses, but what is special about wh-words is that they are also treated as dependents of the following clause; in other words, their relation to the complement verb is one of mutual dependency. This can be seen most easily in an example like (17).

(17) Who came?On the one hand, came depends on who as the latter’s optional complement (optional because it can be omitted by ellipsis, as in the one-word question Who?); but on the other hand, who depends on came as the latter’s subject. This is why wh-words can be described as facing in two directions at the same time: towards the lower clause on the right, and towards the higher clause (typically) on the left. For example, Figure 3 shows the structure for I know who came, using the notation introduced above in which the arrows above the words show landmark relations and those below the words show dependencies; the labels ‘s’, ‘o’ and ‘c’ distinguish subjects, complements and objects. Notice how the landmark relations, even in a simple example like this, are to some extent out of step with the dependency relations, because the mutual dependency of who came is not matched by a mutual landmark relation.

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Figure 3: A simple example of a wh-word.

An additional complication of wh-words is that they allow extraction as an alternative to the subject relation found in who came. This is relevant to pied-piping because prepositional phrases can only be combined with wh-pronouns by extraction. For a simple example of extraction, take

(18) What does she want?Once again, the wh-word what takes a verb (does) as its complement, but the

subject is she, not what; as a dependent of does, what is its ‘extractee’. This provides the expected mutual dependency between what and does, but it also provides a link to want via the dependency between this and does. As extractee of does, what has the option of being a non-extractee dependent of want, and in this case what is the object of want. However, as object it should, by default, follow want, so somehow we have to reconcile the conflict between its default position and its actual position, which is sanctioned by the extraction. The mechanism for this overriding is unclear, but, important though that question is, we can leave it for future restearch. The main claim is that the extractee dependency requires a ‘before’ landmark, and that this requirement overrides the default landmark for any postdependent relation (such as ‘object’). The result is shown in Figure 4.

Figure 4: Extraction overrides default landmarks

Moving towards pied-piping, we must first explain the alternative to pied-piping, which is preposition stranding. This is possible because the extractee relation can

I know who came.

s s

c

o

What does she want?

x

c

x,o

s s

c

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pass recursively down the chain of post-dependents (dependents that follow their parent). We have already seen this possibility in Figure 4, where what is the extractee of does, but can then be ‘passed on’ to want because of the complement link between them, ‘complement’ being a sub-variety of ‘post-dependent’. But once what is recognised as an extractee of want, it has the option of functioning as some kind of post-dependent of this word – hence the additional ‘object’ link between them. In this case the word receiving the extractee is a verb, but it need not be, and if it is a preposition the result is a ‘stranded’ preposition, whose complement is extracted rather than in its default position. Figure 5 shows the structure for the preposition-stranded version of (4), namely (19).

(19) Which drawer do you keep the bank statements in?The main feature to note in this diagram is how which at the beginning of the sentence is linked to in at the end via a chain of extractee dependencies (do – keep – in), which in turn are based on the chain of dependencies which link these words to each other.

Figure 5: Extraction with preposition stranding

We can now return to pied-piping, starting with a functional explanation for this very special construction.

4 Pied-piping in interrogative clauses

Given that prepositions can be stranded, why do we need to be able to pied-pipe them instead? As with all functional explanations, the answer must remain speculative, so all I can hope is that the following sounds plausible. We start with what I believe to be a matter of fact (confirmed by research such as Perera 1984:207-71): English-speaking children learn to pied-pipe prepositions much later than they learn to strand them, and are especially likely to meet pied-piped prepositions in their reading. In short, this construction is evidence of education and literacy, so one simple reason for preferring to pied-pipe a preposition rather than to strand it is to identify oneself as educated. But why do we find pied-piped

Which drawer do you keep the bank statements in?

c s

c

oc

as

a

xx x,c

c

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prepositions in educated writing? Here too there is research evidence from the history of English (Mair and Leech 2006:335) which shows that pied-piping is ‘a more learned Romance overlay on English syntax’. A plausible guess, therefore, is that pied-piping is a learned feature borrowed into English from the high-status French and Latin, where pied-piping is the only option.

The use of preposition pied-piping in any language comes at a cost in terms of processing; indeed it may be that the extra processing cost is part of the attraction of pied-piping, as evidence of linguistic virtuosity. For instance, in saying In which drawer ..., the speaker of (4) had to plan the entire sentence before saying the wh-word, in contrast with Which drawer, which leaves the further development of the sentence completely open; for example, it could have developed into (20) without noticeably changing the content.

(20) Which drawer is the one where you keep the bank statements?In short, pied-piping undoes the benefits of putting the wh-word first so as to define the status of the following clause (as interrogative or relative) before starting to plan the details of this clause’s structure. In contrast, stranding has no effect on the processing at the start of the clause.

Another cost of pied-piping is its effect on word order, where it produces the theoretical conflict discussed above. If the speaker starts with in which drawer, the general theory of word order provides no explanation for the presence of in because in takes its position here from its dependent which. In contrast, the default rule explained above allows dependents to take their parents as landmarks, but not the other way round. However, this is only a default, and the logic of default inheritance allows defaults to be overridden even when they appear to be general theoretical principles. Even if this principle is true of the typical word, wh-words can be different. Moreover, the pattern that overrides the default can be limited in any way, so the special pattern for interrogative wh-pronouns can be limited so that it only applies to prepositions, as in our example in which ....

As for the details of this exceptional pattern, we can be clear about one important point which distinguishes this analysis from those which involve the percolation of features: the pattern is exceptional only in its word order. This means that the exceptionality affects the landmark structure, and not the dependencies. In the case of in which ..., the dependency structure is absolutely normal, and in fact is just the same as for the stranded version of the same sentence except for the lack of an ‘extractee’ link from which to in. The structure is shown in Figure 6. The difference lies in the top left portion of the diagram, where which takes in as its (expected) landmark, and in replaces it as the word which has no landmark. In other words, which has transferred its landmark properties to in. On the model of standard ‘raising’ structures, we can call this pattern ‘landmark raising’. The correct generalisation for interrogative pronouns is that they allow their landmarks to ‘raise’ to a preposition parent.

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Figure 6: A pied-piped preposition

What about the other kinds of pied-piping found in interrogative clauses, involving patterns like those in (6) and (7): how big a hole... and what size shoes...? In these cases, there is no alternative to pied-piping, and the examples seem to have no special stylistic associations with education. Moreover both patterns keep the speaker’s options open through the first two words as they both have simple alternatives:

(21) How big is it?(22) What size is it?

However in both cases we find the same irregular word order as in preposition pied-piping. Landmark raising allows how to transfer its landmark properties either to big or a step further, up to a, and similarly it allows what to do the same to its parent, shoes. The precise details of these analyses remain to be explored; for instance, is the rule for how big a part of a more general pattern which underlies so big a and too big a? And what other nouns allow landmark raising from what? However, the general outlines of the analysis seem reasonably clear.

In which drawer do you keep the bank statements?

c s

c

oc

as

a xx

cc

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5 Pied-piping in relative clauses

As we have seen, the main outlines of pied-piping apply as much to relative clauses as to interrogative clauses. In particular, relative pronouns allow the same preposition pied-piping as we have already discussed for interrogative clauses. The two other patterns of interrogative clauses, involving how and what, do not apply to relative clauses because these two pronouns are only interrogatives. Simple preposition pied-piping is found in examples like (8), the curtain behind which Kim was hiding. The analysis is the same, mutatis mutandis, as for the equivalent interrogative: Behind which curtain was Kim hiding?, with behind taking over the role of which as the landmark for the rest of the sentence. This is a very straightforward example of landmark raising.

This seems to be the only possibility for pied-piping in restrictive relative clauses. (Whose is sometimes listed as an example of pied-piping, but in WG it is the head of its phrase.) Non-restrictive relative clauses are very different. Not surprisingly, perhaps, they are much more like main clauses, and it is tempting to see pied-piped examples as a mixture of ordinary topicalisation with relative-clause marking. For example, consider again examples (9) to (13), repeated below.

(23) She’s just sat her final exam, the result of which we expect next week.(24) They will be involved in several projects, one of the most important of

which will be to find ways to use the new superconductor in chips that can provide the brains of a new generation of supercomputers.

(25) The many varieties of mammalian skin secretions perform a wide range of functions, prominent among which is sexual attraction.

(26) I became disturbed by a ‘higher criticism’ of the Bible, to refute which I felt the need of a better knowledge of Hebrew and archaeology.

(27) They take a rigorous examination, passing which confers on the student a virtual guarantee of a place at the university

These examples give an even stronger sense of syntactic virtuosity, an almost conscious attempt to exploit topicalisation in relative-clause formation. Every one of the examples can be parallelled by a main clause with a full noun instead of which:

(28) The result of this exam we expect next week.(29) One of the most important of these projects will be to find ways to use the

new superconductor in chips that can provide the brains of a new generation of supercomputers.

(30) Prominent among these functions is sexual attraction.(31) To refute this criticism I felt the need of a better knowledge of Hebrew and

archaeology.(32) Passing this examination confers on the student a virtual guarantee of a

place at the university

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The pied-piped examples offer serious challenges for processing because the writer and reader both have to maintain all the pied-piped words in working memory while waiting for the link, via which, to the preceding noun. The underlying grammar is also unclear, given the possibility that there are no constraints on this kind of pied-piping beyond those of topicalisation.

As for the mechanics of the syntactic analysis, landmark raising still seems appropriate. Figure 7 compares the syntactic structures of two non-restrictive relative clauses without and with pied-piping. Notice how the dependencies and landmark relations around which in the simpler example are redistributed in the more complex one.

Figure 7: Non-restrictive relatives without and with pied-piping

6 Conclusions

This study of pied-piping in English has led to an important theoretical conclusion about the relation between word order and dependencies: they are autonomous, not in the sense that they can vary independently but in the sense that they require two separate sets of relations among words. On the one hand we have the familiar dependency relations of syntax, including those relations such as ‘extractee’ that allow variations on default word orders; and on the other hand, we have the relations of word order, with ‘before’ and ‘after’ as sub-divisions of the basic relation ‘landmark’. There are strong default relations between the two sets, with

She took the exam, which she enjoyed.

She took the exam, the result of which she enjoyed.

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dependents typically taking their parent as their landmark. But there are exceptions which show how important it is to separate the two sets of relations. General theoretical exceptions (not discussed in this paper) include the ‘raising principle’, which requires a word which has two parents, one depending on the other, to take the higher of the two as its landmark. But there are also parochial exceptions which disrupt the regular mapping between dependencies and landmark relations, and one of these is pied-piping.

The proposed analysis locates all the irregularity of pied-piping in the word order, so that the book in which I found it has almost the same dependency structure as the book which I found it in, but maps this structure onto a different set of word order relations so that in takes its position from which in one but from found in the other. In terms of general theory, this irregularity does not require any special apparatus beyond the existing resources for default inheritance combined with the distinction between dependency structure and word order.

This analysis seems to explain the facts better than one which invokes upwards percolation of the wh-feature. Not only does this require theoretical apparatus which is not otherwise required – upward percolation from a non-dependent – but it locates the irregularity in the wrong place: in the classification, not in the word order.

The distinction between word-order and dependency relations lies at the heart of the analysis of pied-piping. This distinction is easily made in a network-based theory such as Word Grammar, where word order can be – indeed, has to be – treated as a relation. It is less obvious that it is possible in other theories which rely on the left-right dimension of our writing system to handle linear precedence.

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References

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