PARSING AND INTERPRETING COMPARATIVES 
Marmy Rayner 
SICS 
Box 1263, S-164 28 KISTA 
Sweden 
Amelie Banks 
UPMAIL 
Box 1205, S-750 02 UPPSALA 
Sweden 
Tel: +46 8 752 15 O0 Tel: +46 18 181051 
ABSTRACT 1. INTRODUCTION 
We describe a fairly 
comprehensive handling of the 
syntax and semantics of 
comparative constructions. The 
analysis is largely based on the 
theory developed by Pinkham, 
but we advance arguments to 
support a different handling of 
phrasal comparatives - in 
particular, we use direct 
interpretation instead of C- 
ellipsis. We .explain the reasons 
for dividing comparative 
sentences into different categories, 
and for each category we give an 
example of the corresponding 
Montague semantics. The ideas 
have all been implemented 
within a large-scale grammar for 
Swedish. 
This paper is written with two distinct 
audiences in mind. On the practical 
side, we try to present a cookbook 
which the natural language interface 
implementor can ~use if he wishes to 
incorporate comparative constructions 
into his system's coverage. This is, we 
trust, interesting in itself; a quick 
glance at Table 1 should be enough to 
show that this construction is more 
common than is perhaps generally 
realized. Thus in addition to the 
obvious more, less and as much as, 
used together with an adjective, adverb 
or determiner, we also include such 
words as same, before and after, used 
in appropriate ways. We also try to 
give a usable classification of the 
various kinds of constructions 
generally lumped together under the 
blanket heading of "Comparative 
Ellipsis". 
Examples of comparatives 
1) John is taller than Mary. 
2) Few people run as fast as John. 
3) John bought more books than Mary. 
4) John was happier in New York than in London. 
5) John has more books than Mary has newspapers. 
6) John had this job before me. 
7) John was born in the same city as Mary. 
8) Mary had more friends than John thought. 
9) More men than women bought the book. 
10) Mary seems brighter than most of the pupils. 
Adjectival comparison 
Adverbial comparison with "as" 
Determiner comparison 
Comparison on PP 
Clausal comparison 
"Before" comparison 
"Same" comparison 
"S-operator" comparison 
Complex comparative determiner 
"Simple" phrasal comparison 
Table I 
49 
On the theoretical side, we want to 
reexamine some fundamental 
questions concerning the nature of the 
comparative construction; we are 
going to argue that our practical work 
fairly strongly supports a hypothesis 
that has already appeared in several 
forms in the theoretical literature, 
namely that "comparative ellipsis" is a 
semantic rather than syntactic 
phenomenon. We expand more on 
this theme in section 2. In section 3 we 
present our handling of clausal 
comparison, which is a straightforward 
implementation of Pinkham's theory. 
The next two sections cover non- 
clausal comparison, and constitute the 
main part of the paper. In section 4 we 
show how Pinkham's predicate 
copying analysis can be implemented 
within a Montague grammar 
framework so that duplication of 
material is not syntactic copying of 
parts of the parse-tree but is instead a 
double application of a higher level 
function. We demonstrate at length 
how this method can be used to handle 
three different kinds of elliptic 
construction, all of which present 
problems for the syntactic approach. In 
section 5 we describe our treatment of 
the base generated phrasal 
constructions from section B.2.3 of 
Pinkham's thesis. (We call these 
"simple" phrasal comparatives). In the 
final section we summarize our 
results; in particular we address 
ourselves to the question of justifying 
our classification of comparatives into 
separate categories instead of providing 
a unified interpretation. 
The current paper is a shortened 
version of (Rayner & Banks 88) ("the 
full paper"), which we will refer to 
from time to time. This includes 
among other things test examples and 
full program listings of a logic 
grammar based on the SNACK-85 
implementation, which covers all 
forms of comparison discussed here. 
2. PREVIOUS WORK 
The traditional viewpoint has been to 
explain non-clausal comparatives by 
means of deletion rules; the first 
detailed account based on this idea was 
(Bresnan 73), which strongly 
influenced most work in the area 
during the following ten years. 
Recently, however, other researchers 
have pointed out problems with 
Bresnan's approach; a very thorough 
and detailed criticism appears in 
(Pinkham 85) 1, which has been our 
main theoretical source. Pinkham 
gives examples of a wide range of 
constructions which are difficult or 
impossible to explain in terms of 
deletion phenomena, and suggests 
instead an approach in which at least 
some comparative constructions are 
base-generated phrasal and then 
interpreted using a rule which she calls 
"distributive copying". The following 
example 2 shows how the scheme 
works in practice. Sentence la) receives 
the logical form lb): 
la) I invited more men than women 
lb) I INVITED (MORE \[ql (ql men), q2 
(q2 women)\]) 
1 Hereafter "Pinkham". 
2 From Pinkharn, p. !23 
50 
(The object of INVITED is the base 
generated phrasal). After distributive 
copying, this becomes lc): 
lc) MORE I ql (INVITED ql men), q2 
(INVITED q2 women)\] 
This manoevre, replacing syntactic 
deletion rules with interpretative 
copying operations, seems to us very 
powerful, and (although we formulate 
it in a rather different way) is one of 
the central ideas in our own treatment 
of comparatives. We have in fact taken 
it even further than Pinkham, who 
keeps the verb deletion rule of "C- 
ellipsis" to explain some comparative 
constructions: in the account presented 
below in section 4, we get rid of the 
deletion rules completely and use only 
interpretative methods. 
In this context, it is interesting to look 
at Levin's LFG-based work on sluidng 
constructions (Levin 82). Levin 
presents a variety of arguments to 
support her claim that sluicing is not a 
c-structure phenomenon (i.e. not 
elliptic in nature), but rather 
explainable at f-structure level (i.e. in 
some sense related to a semantic 
copying operation). The differences 
between sluicing and comparative 
ellipsis are sufficiently great that this 
cannot in itself be said to prove 
anything, but it is none the less 
indicative of the way in which 
linguists are thinking about these 
problems. 
In SNACK-85, which uses a framework 
based on that in (Pereira 83), we 
perform copying operations on "quant- 
trees", a level of structure which can 
loosely be compared with Chomskian 
logical form or LFG's f-structures. 
Viewed in this light, we claim that our 
treatment of non-clausal comparison 
(which at first glance might seem 
somewhat ad hoc) is in fact fairly weU- 
related to current tendencies in 
theoretical linguistics. 
3. CLAUSAL COMPARATIVES 
Most authors are agreed that the case of 
clausal comParison is the simplest, and 
for this reason we tackle it first; despite 
this, it will be seen that there are a few 
tricky points. Our analysis is heavily 
based on Pinkham's, and virtually 
amounts to an implementation of the 
second section of her thesis; we start by 
summarizing what we see as the main 
ideas in her treatment. 
The fundamental notion in Pinkham's 
analysis is to assume that there is an 
implicit element present in a 
comparative clause, which is linked to 
the head of the comparison 1 in a way 
similar to that in which a trace or gap 
is linked to its controller. This "trace" 
always contains a quantifier-like 
component. (We will adopt Pinkham's 
notation and symbolize this as Q). It 
may consist of just the Q on its own, or 
else be an implicit NP composed of the 
Q together with other material from 
the head of the comparison. 
Pinkham argues that there are 
essentially three cases; these are 
exemplified in sentences 2a) - 2c). In 
the first of these, just the Q is 
extraposed; in the second, a Q together 
with the CN books, taken from the 
1 We endeavour throughout this paper to keep our 
terminology as close as possible to that used by 
Pinkham. The terms used are summarized in 
Appendix 1. 
51 
head more books. If the head contains 
a comparative adjective, as in 2c), then 
the extra material, consisting of the 
adjective and the main noun from the 
head, is obligatory. For a justification, 
and an explanation of several apparent 
exceptions, we refer to Pinkham, p. 33 - 
40. 
2a) John bought more books than 
Mary bought (Q) records. 
2b) John bought more books than 
Mary could carry (Q books). 
2c) John bought a more expensive 
vase than Mary bought (a Q 
expensive vase). 
A scheme of this kind can readily be 
implemented using any of the 
standard ways of handling traces. In 
our system, which is based on 
Extraposition Grammar (Pereira 83), 
we use the "extraposition list" to move 
the material from the head to the place 
in the comparative clause where it is 
going to appear; this corresponds to use 
of the HOLD register in an ATN, or 
"slash categories" in a GPSG-like 
framework. 
Although this method appears to work 
well in practice, thre is a theoretical 
problem arising from the possibility of 
sentences with crossing extrapositions. 
We refer to the full paper for further 
discussion. 
4. DIRECT INTERPRETATION OF 
NON-CLAUSAL COMPARISON 
4.1 Basic ideas 
Our first implementation (Banks 86) 
was based on the conventional 
interpretation of comparatives: all 
comparatives are explicit or elliptic 
forms of clausal comparatives, making 
the analysis of comparison essentially a 
syntactic process. In (Banks & Rayner 
87) we presented this in outline and 
then described some problems we had 
encountered, which eventually caused 
us to abandon the approach. Briefly, it 
turned out that the exact formulation 
of the syntactic copying process was by 
no means straightforward: there 
appeared to be a strong parallel with 
the well-known arguments against the 
analogous point of view for co- 
ordination constructions. (See e.g. 
(Dowty et. al. 82), p. 271). As an 
example, we presented sentence 3) 
3) Everyone spent more money in 
London than in New York. 
which is problematic for a reduction 
account. We suggested instead that the 
sentence be thought of as being 
composed of the following 
components: the initial everyone, the 
contrasted elements London and New 
York, and the duplicated part, which 
could be rendered (roughly) as is a P 
such that P spent an amount of money 
in where _. In a Montague- 
grammar-like formalism, this can then 
be given the following semantic 
analysis: 
52 
"Montagovian" analysis of comparative 
(spent(x,y,z) is to be read as "x spent amount y in the city z") 
than in New York 
1. everyone 
2. New York 
3. London 
4. spent m in 
5. spent more in 
6. spent more in London than in New York 
everyone spent more in London than 
in New York 
Table 2 
. 
~.QVx: person(x)--)Q(x) 
~.QBz: \[z=New YorkAQ(z)\] 
~.QBz: \[z=LondonAQ(z)\] 
~.y~XzXx: spent(x,y,z)AP(y) 
XzXx3y: spent(x,y,z)A 
By': spent(x,y',New York)Ay>y' 
Xx.~y: spent(x,y,London)A 
By':spent(x,y',New York)Ay>y' 
Vx: person(x)~ 
\[3y: spent(x,y, London)A 
3y': spent(x,y',New York)Ay>y'\] 
The key point is that the syntactic 
copying of the deletion approach has 
been replaced by a semantic operation, 
a double instantiation of a lambda- 
bound form. The following account 
summarizes how the idea is 
implemented within the structure of 
the SNACK-85 system. 
Semantic interpretation in SNACK-85 
is performed by first converting the 
parse-tree to an intermediate form, 
which we call (following (Pereira 83)) a 
quant-tree. This is then subjected to 
rewriting rules before being converted 
into the final logical form. Normally, 
these rewriting rules formalize so- 
called scoping transformations; here, 
we will also use them to describe the 
interpretation of non-clausal 
comparison. The basic motivation is 
the same, namely to remove rules 
from the grammar which lack syntactic 
motivation. 
We introduce four new kinds of nodes 
in addition to those defined in (Pereira 
83): we call these comparands, 
comparative-objects, comparisons, and 
comparison-placeholders. They 
interact as follows. 
(Stage 1) At the syntactic level, we view 
the comparative object as a constituent 
in its associated comparative AP; when 
the parse-tree is transformed into the 
quant-tree, the AP gets turned into a 
comparand node, in which there is a 
comparative-object subnode 
representing the comparative object. 
(Stage 2)Rewriting rules then move 
the comparative-object out of the 
comparand, leaving behind a 
placeholder. This is a triple consisting 
of the compared predicate (the 
adjective, adverb or whatever), and 
two logical variables (the "linking" 
variables), which correspond to the 
lambda-bound variables y and ~ above. 
(Stage 3) The "raised" comparative- 
object node is a 4-tuple. It consists of 
53 
• The two variables y and P (and is 
thus "linked" to the placeholder 
through them- hence the name), 
• The comparison type (more than, 
less than, same as etc.) 
• The quant subnode which 
represents the comparand NP or 
PP. 
The rewriting rules move it upwards 
until it finds a quant node that it can be 
compared against. At the moment, the 
only compatibility requirements are 
that the quant node and the 
comparative-object's quant subnode 
not have incompatible case-markings. 
This could be improved upon; one way 
would be to define preference 
heuristics which gave higher priority 
to comparisons between quant nodes 
whose variables are of similar type. 
The result of merging the two nodes is 
a comparison node, which is a 5-tuple 
consisting of 
• The comparative-object's quant 
node 
• The quant node it has been 
merged with 
• The comparison type 
• The two "linking variables", y 
and P 
When the quant-tree is converted into 
logical form, there should thus be only 
comparison nodes and placeholder 
nodes left, with the placeholders 
"below" the comparisons. In the final 
stage, the portion of the quant-tree 
under the comparison node is 
duplicated twice, and the linking 
variables instantiated in each copy in 
the manner described above. So in the 
"inner" copy, P gets instantiated to a a 
form 2y:comp(y,y'), where comp is the 
type of comparison and y and y' are the 
degree variables; in the "outer" copy, P 
is instantiated to the value of the inner 
form. 
In the next two subsections, we go 
further to show how a similar analysis 
can be used to assign a correct 
semantics to two other kinds of 
comparative construction without any 
recourse to C-ellipsis. 
4.2. Comparatives with "s-operators" 
In this section, we are going to 
examine comparative constructions 
like those in 4a), 4b) and 4c). These 
have a long and honourable history in 
the semantics literature; 4c) is a famous 
example due to Russell. 
4a) Mary had more friends than John 
had expected. 
4b) Most people paid more than Mary 
sa/d. 
4c) John's yacht was longer than I 
thought. 
In order tohandle examples like these 
within our framework, we need a 
syntactic representation which does 
not involve ellipsis. Our solution is to 
introduce a syntactic constituent which 
we call an "s-operator": we define this 
implicitly by saying that an "s- 
operator" and a sentential complement 
combine to form a clause. 1 Thus the 
italicized portions of the sentences 
above are deemed to be s-operators, 
and in each of them the s-operator's 
1 In a categorial grammar framework like HPSG 
(Pollard & Sag 88), we could simply identify an s- 
operator with a constituent of the form S/S-COMP. 
It is fairly straightforward to define s-operators in 
XG-grammar. 
54 
missing complement is viewed as a 
kind of null pronoun. 
Although this move may in English 
seem syntactically quite unmotivated, 
there are other languages where 
evidence can be found to support the 
claim that these pronouns really exist. 
In Russian, where comparative 
constructions very closely follow the 
English and Swedish patterns, they can 
optionally appear in the surface 
structure as the pronoun ~ 1"0. The 
following sentence illustrates this. 
OH K~H'I'I4,rl 60JII, LUe KHWr qeH ~ 3TO 
He bought more books than I ~T0 
n~Ma~. 
thought. 
Semantically, the analysis of such 
sentences is exactly parallel to that in 
the preceding subsection. Comparing 
4b) with 3), the "initial part" is most 
people, and the "contrasted elements" 
are the s-operator Mary said and an 
implicit trivial s-operator which we 
can write as (it is true that). The 
"duplicated part" is the predicate is a P 
such that P paid amount of money 
where . We can sketch a 
"Montagovian" analysis similar to that 
in table 2 
"Montagovian" analysis of s-operator comparative 
(paid(x,y) is to be read as "x paid y amount of money") 
1. most people 
2. Mary said 
3. (it is true tha0 
4. paid 
5. paid more than Mary said 
6. (it is true tha0 paid more than Mary said 
7. most people paid more than Mary said 
~.Q: most0~x:person(x).Q) 
~.Q: said(m,Q) 
~.y~.~ Xx: paid(x,y),<P(y) 
~,x3y paid(x,y)A 
By'said(m,paid(x,y')Ay>y') 
~.x3y paid(x,y)A 
3y'said(m,paid(x,y')Ay>y') 
most(~x:person(x), 
Xx: 3y: paid(x,y)A 
3y'said(m,paid(x,y')A 
y>y') 
Table 3 
The implementation of this analysis in 
terms of quant-tree rewriting rules 
involves only a slight extension of the 
method described in section 4.1 above. 
The reader is referred to the program 
code in the full paper for the concrete 
details. 
55 
4.3. "Parallel" phrasal comparatives 
Comparative constructions of the type 
illustrated in 5a) have been the object 
of considerable controversy. The 
orthodox position was that they were 
"parallel" constructions: 5a) would 
thus be a reduced form of 5b). 
5a) More women than men read 
'1-Iouse and Garden". 
5b) More women read "House and 
Garden" than men read "House 
and Garden". 
Pinkham, however, gives good reasons 
for supposing that this is not the case, 
and that the construction is in some 
sense base generated phrasal (p.121- 
123). It will presumably not come as a 
revelation to hear that we agree with 
this idea, though we express it in a 
somewhat different way. 
Our interpretation of Pinkham's 
analysis recasts the more ... than... 
construction as a special kind of 
determiner. We introduce an extra 
rule for NP formation: in addition to 
the normal NP --~ Det + CN, we also 
have NP --~ CompDet + CN + CN. (The 
details can be found in the full paper). 
This allows us as usual to give the 
constituent structure without use of 
ellipsis, and then to interpret it using a 
suitable predicate-copying operation. 
Once again we illustrate with a 
Montague-style example. 
"Montagovian" analysis of "paraUel" phrasal comparative 
(reads(x,y) is to be read as "x habitually reads y") 
1. women 
2. men 
3. more 
4. more women than men 
5. "House and Garden" 
6. read "House and Garden" 
7. more women than men read 
"House and Garden" 
~: woman(x) 
~x: man(x) 
XP~.QM~ more(P, Q, R) 
M~,: more(~x: women(x), Xx: men(x), R) 
~.x: x = "H & G" 
Xx: read(x,y) n y ="H & G" 
more( ~x: women(x), Xx: men(x), 
~x: read(x,"H & G")) 
Table 4 
It is interesting to compare our 
treatment with that suggested in 
(Keenan & Stavi 86) (p.282-284) for 
comparative adjectival constructions 
like that in 6a); they argue 
convincingly that these are to be 
regarded as directly interpreted, rather 
than as "reduced forms" of sentences 
like 6b). It seems to us that their 
arguments can be adapted to support 
the analysis of "parallel" phrasals 
given above; so if we were to extend 
their example, we would have that 6b) 
in its turn was also to be interpreted 
directly, rather than considered a 
reduction of 6c). 
6a) More male than female students 
passed the exam. 
56 
6b) More male students than female 
students passed the exam. 
6c) More male students passed the 
exam than female students passed 
the exam. 
5 "SIMPLE" PHRASAL 
COMPARATIVES 
We finally turn our attention to a third 
type of comparative construction, 
which does not properly seem to fit 
into any of the patterns given above. 
We start by giving in 7) - 9) some 
examples of the kind of sentence we 
have in mind. 
7) Mary seems brighter than most 
pupils. 
8) He ran faster than the world record. 1 
9) John needs a bigger 2 spanner than 
the No. 4. 
Pinkham uses constructions like these 
as her key examples when 
demonstrating the existence of base- 
generated phrasal comparatives. 
Looking for instance, at 9), we claim 
with Pinkham that the most natural 
solution is to treat bigger spanner than 
the No. 4 as a dosed constituent with a 
semantic interpretation which does 
not involve the rest of the sentence. 
It may not be obvious at first why this 
should be so, and we pause briefly to 
examine the possible alternatives. 
Firstly, suppose that we tried to use a 
reduction/predicate copying account. 
This would make 9) a form of 9a): 
9a) John needs a (big to extent X) 
spanner, X such that John needs 
the (big to extent Y) No. 4. spanner, 
X>Y. 
implying that John needs the No. 4. 
This is clearly wrong; the "needs" isn't 
copied in any way, and in fact the scope 
of any copying operation must be 
limited to the phrase bigger spanner 
than the No. 4. If we are absolutely 
bent on using copying, it appears to us 
that the only way in which it can be 
done is to treat 9) as derived from 9c) 
through 913) 
9b) John needs a spanner which is 
bigger than the No. 4. 
9c) John needs a spanner which is (big 
to extent X), X such that the No. 4 
is (big to extent Y), X > Y. 
To be honest, we can't completely 
discount this approach. However, since 
it makes bigger than the No. 4 into a 
constituent in the intermediate 9b), we 
think it simpler to interpret the phrase 
structure directly, as is illustrated in 
the following Montagovian analysis. 
1pinkham's example 124a, p. 136 
2 We will treat "bigger" as though it were actually 
"more big" for the usual reasons. 
57 
Montagovian analysis of "simple" phrasal comparative 
(needs(x,y) to be read as "x needs something of which the predicate y holds") 
1. John 
2. needs 
3. No. 4 
4. big 
5. spanner 
6. the 
7. more 
8. more big than the No. 4 
9. a bigger spanner than the 
No. 4 
10. John needs a bigger spanner 
than the No. 4 
Xx: x = John 
Xx,y: needs(x,y) 
X.x: type_of(x, No. 4) 
Xx,y: big(x,y) 
Xx: spanner(x) 
XP~.Q: the(P, Q) 
XP~.QX.~.: (X.x: By: P(x,y) A 
R(Q, Xz: By': P(z,y') (y > y')) 
X.x: 3y: big(x,y) A 
• the(Xz: type_of(x, No. 4), 
kz: 3y': big(z,y') A (y > y')) 
Ix: spanner(x) ^ 
3y: big(x,y) a 
the(Xz: type_of(x, No. 4), 
Xz: 3y': big(z,y') ^ (y > y')) 
needs(John, 
~: spanner(x) ^ 
3y: big(x,y) A 
the(Xz: type__of(x, No. 4), 
kz: 3y': big(z,y') A (y > y')) 
Tables 
It will be apparent that bigger than the 
No. 4 turns up as a constituent here 
too, and thus our solution is in a sense 
equivalent with the alternate one 
proposed above. This is a striking 
illustration of the difficulties that can 
attend any efforts to make rigorous 
comparisons between different 
syntactic-semantic analyses of natural- 
language constructions. 
6. CONCLUSIONS 
We have presented a method for 
syntactic and semantic interpretation 
of comparative sentences. This has 
been done by dividing our material 
into three separate groups, each of 
which are treated differently: 
Clausal comparatives (section 3), 
which are handled by extraposing 
a constituent containing a Q, 
following Pinkham's theoretical 
analysis. 
58 
• Phrasal comparatives (section 4), 
treated by direct interpretation 
using "predicate copying". 
• "Simple" phrasals (section 5), 
handled by a different direct 
interpretation method. 
We do not claim that this classification 
is the only way to explain the facts; as 
we have said above, it would be 
possible to rewrite simple phrasal 
comparatives into directly interpreted 
phrasal comparatives, and also to 
rewrite directly interpreted phrasal 
comparatives as clausal comparatives. 
We think, however, that this 
manoevre would give us nothing in 
the form of real gains; even though a 
unified solution might seem more 
elegant, the syntactic transformations 
needed are more complicated than the 
use of different categories. Thus our 
first argument against a unified 
approach is the practical one: we need 
do less work as implementors if we 
adopt the classification described here. 
Despite this, we suspect that many 
readers (especially those more 
theoretically than practically inclined) 
would find it comforting to have some 
direct evidence that supports our point 
of view. In this connection we think 
that the following data from Swedish 
may be of interest. 
Comparative constructions in Swedish 
are virtually identical to the 
corresponding ones in English. One 
significant difference, however, is the 
distribution of the relative pronoun 
vad ("what"); this can optionally be 
inserted after the comparative marker 
in some constructions, as shown in I0) 
and 11) I . 
10) Johan k6pte tier b6ckex /in 
John bought more books than 
(vad) Maria gjorde. 
(what) Mary did. 
11) Johan bar ett dyrare 
John has a more expensive 
hus ~in (vad) jag har. 
house than (what) I have. 
Given the correspondences between 
clausal comparison and relative 
clauses described in section 4, it is very 
tempting to account for the "vad" as a 
relative pronoun realizing the 
normally null Q. If we are prepared to 
accept this, it then appears significant 
that "vad" may not be used in most 
phrasal comparatives, as shown in 12) 
and 13). This would seem problematic 
for a transformational account, but is 
quite natural if phrasal comparatives 
are treated by direct interpretation; 
there isn't any Q, so it can't be realized 
as a "vad". 
14) \]ohan k6pte tier b6cker /in 
John bought more books than 
(*vad) Maria. 
(*what) Mary. 
15) Flex kvinnor iin (*vad) 
More women than (*what) 
1/isex "H/int i Veckan". 
read "News of the World". 
m~n 
men 
There is, however, one exception to 
the rule: "vad" may appear in the "s- 
1 This is also possible in some dialects of English. 
$9 
operator" constructions from section 
5.1 above, as shown in 16). 
16) Johan k6pte tier b6cker gn 
John bought more books than 
(vad) Maria troclde. 
(what) Mary thought. 
We are not certain how to explain 
this, and leave the reader to judge the 
facts for himself1; but despite this 
irregularity, we think the other data 
gives our theory a considerable 
amount of concrete backing. 
APPENDIX: TERMINOLOGY 
Comparative Clause: the clause 
introduced by the comparison marker. 
Compared Element: the largest 
constituent in the main or the 
comparative clause, the leftmost 
element of which is a comparison 
marker or the comparative quantifier 
Q. 
Comparison Marker: words like than, 
as, before, after. 
Head of the Comparison: refers to the 
compared element in the main clause. 
Phrasal Comparative: a comparative 
complement which appears to be the 
reduced form of a comparative clause. 
This may be a remnant of the 
application of Comparative Ellipsis to a 
comparative clause, or it may be base 
generated. 
Q: An (implicit or explicit) comparison 
quantifier which is extraposed in the 
interpretation of clausal comparatives. 
REFERENCES 
(Banks 86) Banks, A. Modifiers in Natural 
Language, Bachelor's Thesis, Uppsala 
University, 1986. 
(Banks & Rayner 87) Banks, A. and Rayner, M., 
Comparatives in Logic Grammars - Two 
Viewpoints, Proceedings of the 2rid 
International Workshop on Natural Language 
Understanding and Logic Programming, p. 131 - 
137,1987 
(Bresnan 73) Bresnan, J. Syntax of the 
Comparative Clause Construction in English, 
Linguistic Inquiry 4, p. 275-343,1973 
(Dowty et al. 82) D. Dowty, R.E. Wall and S. 
Peters, introduction to Montague Semantics D. 
Reidel, 1982 
(Keenan & Stavi 86) Keenan, E.L and Stavi J. 
Natural Language Determiners, Linguistics and 
Philosophy 9, p. 253-325 
(Levin 82) Levin, L., Sluicing: A Lexical 
Interpretation Procedure, in Bresnan, J. (ed.) 
The Mental Representation of Grammatical 
Relations, MIT Press, 1982 
(Pinkham 85) Pinkham, J. The Formation of 
Comparative Clauses in French and English, 
Garland Publishing Inc., New York, 1985 
(Pereira 83) Pereira, F.N.C. Logic for Natural 
Language Analysis, SKI Technical Note No 275, 
1983 
(Pollard & Sag 88) C. Pollard and I. Sag, 
Information-based Syntax and Senmantics, Vol. 
1, CSLI, 1988 
(Rayner & Banks 86) Rayner, M. and Banks, A. 
Temporal Relations and Logic Grammars, 
Proceedings of ECAI-86, VoL 2 p.9-14" 1986 
1 One possibility is that this is a result of cognitive 
limitations in the human sentence-processing 
mechanism, since an arbitrary amount of text can 
separate a "vad" from the realization that the 
construction is s-operator rather than clausal 
comparison. 
60 
