Multilingual design of EuroWordNet 
Piek Vossen, University of Amsterdam 
Pedro Diez-Orzas, University of Madrid Alfonso X E! Sabio 
Wim Peters, University of Sheffield 
Abstract 
This paper discusses the design of the 
EuroWordNet database, in which semantic data- 
bases like WordNetl.5 for several languages are 
combined via a so-called inter-lingual-index. In 
this database, language-independent data is 
shared and language-specific properties are 
maintained as well. A special interface has been 
developed to compare the semantic configura- 
tions across languages and to track down differ- 
ences. The pragmatic design of the database 
makes it possible to gather empirical evidence 
for a common cross-linguistic ontology. 
1 Introduction 
EuroWordNet is an EC-funded project (LE2-4003) that 
aims at building a multilingual database consisting of 
wordnets in several European languages (English, 
Dutch, Italian, and Spanish). Each language specific 
wordnet is structured along the same lines as WordNet 
(Miller90), i.e. synonyms are grouped in synsets, which 
in their turn are related by means of basic semantic rela- 
tions. 
The EuroWordNet database will as much as possible 
be built from available existing resources and databases 
with semantic information developed in various projects. 
This will not only be more cost-effective but will also 
make it possible to combine information from independ- 
ently created resources, making the final database more 
consistent and reliable, while keeping the richness and 
diversity of the vocabularies of the different languages. 
For that purpose the language-specific wordnets will be 
stored as independent language-internal systems in a 
central lexical database while the equivalent word 
meanings across the languages will be linked to each 
other. 
The multilingual nature of this conceptual database 
raises methodological issues for its design and develop- 
ment. First there is the question of which architecture to 
adopt. We have considered four possible designs: 
a) Linking by pairs of languages. 
b) Linking through an structured artificial language 
c) Linking through one of the languages 
d) Linking through an non-structured index 
The first option (a) is to pair-wise link the languages 
involved. This makes it possible to precisely establish 
the specific equivalence relation across pairs of lan- 
guages, but it also multiplies the work by the number of 
languages to be linked. Furthermore, the addition of a 
new language will ask for the addition of new equiva- 
lence relations to all the other languages, with all the 
possible consequences. The second option (b) is to link 
the languages through an structured language-neutral 
inter-lingua. A language-independent conceptual system 
or structure may be represented in an efficient and accu- 
rate way but the challenge and difficulty is to achieve 
such a meta-lexicon, capable of supplying a satisfactory 
conceptual backbone to all the languages. A drawback 
from a methodological point of view is that new words 
that are added in one of the languages might call for a 
revision of a part of the language-independent network. 
As a third possibility the linking can be established 
through one of the languages. This resolves the incon- 
veniences and difficulties of the former two options, but 
forces an excessive dependency on the lexical and con- 
ceptual structure of one of the languages involved. The 
last possibility (d) is to link through a non-structured list 
of concepts, which forms the superset of all concepts 
encountered in the different languages involved. This list 
does not satisfy any cognitive theory, because it is an 
unstructured index with unique identifiers for concepts 
that do not have any internal or language-independent 
structure. This has the advantage that it is not necessary 
to maintain a complex semantic structure that incorpo- 
rates the complexity of all languages involved. Further- 
more, the addition of a new language will minimally 
affect any of the existing wordnets or their equivalence 
relations to this index. 
For pragmatic reasons we have chosen design (d). An 
unstructured index as a linking device is most beneficial 
with respect to the effort needed for the development, 
maintenance, future expansion and reusability of the 
multilingual database. Of course the adopted architecture 
is not without its difficulties. These are especially cru- 
cial in the process of handling the index and creating 
tools for the developers to obtain a satisfactory result. 
Tasks such as identifying the right inter-hngual corre- 
spondence when a new synset is added in one language, 
or how to control the balance between the languages are 
good examples of issues that need to be resolved when 
this approach is taken. 
In this paper we will further explain the design of the 
database incorporating the unstructured multilingual 
index. The structure of this paper is then as follows: first 
we will describe the general architecture of the database 
with the different modules. In section 3 we will discuss 
how language-specific relations and complex- 
equivalence relations are stored. Finally, section 4 deals 
with the specific options to compare the wordnets and 
derive information on the equivalence relations and the 
differences in wordnet structure. 
2. High-level Design of the EuroWord- 
Net Database 
All language specific wordnets will be stored in a central 
lexical database system. Each wordnet represents a lan- 
guage-internal system of synsets with semantic relations 
such as hyponymy, meronymy, cause, roles (e.g. agent, 
patient, instrument, location). Equivalence relations 
between the synsets in different languages and Word- 
Netl.5 will be made explicit in the so-called Inter- 
Lingual-Index (ILI). Each synset in the monolingual 
wordnets will have at least one equivalence relanon with 
a record in this ILI. Language-specific synsets linked to 
the same ILI-record should thus be equivalent across the 
languages. The ILI starts off as an unstructured list of 
WordNetl.5 synsets, and will grow when new concepts 
will be added which are not present in WordNetl.5 (note 
that the actual internal organization of the synsets by 
means of semantic relations can still be recovered from 
the WordNet database which is linked to the index as 
any of the other wordnets). The only organization that 
will be provided to the ILI is via two separate ontologies 
which are linked to ILl records: 
• the top-concept ontology: which is a hierarchy of 
language-independent concepts, reflecting explicit 
opposition relations (e.g. Object and Substance). 
• a hierarchy of domains labels which relate concepts 
on the basis of scripts or topics, e.g. "sports", "water 
sports", "winter sports", "military", "hospital". 
Top-Ontology 
Figure 1. 
Both the top-concepts and the domain labels can be 
transferred via the equivalence relations of the hiLl- 
records to the language-specific meanings and, next, via 
the language-internal relations to any other meaning in 
the wordnets, as is illustrated in Figure 1 for the top- 
concepts Object and Substance. The ILl-record object is 
linked to the Top-Concept Object. Since the Dutch syn- 
set voorwerp has an equivalence-relation to the ILl- 
record the Top-Concept Object also applies to the Dutch 
synset. Furthermore, it can be applied to all Dutch syn- 
sets related via the language-internal relations to the 
Dutch voorwerp. 
Both hierarchies will enable a user to customize the 
database with semantic features without having to access 
the language-internal relations of each wordnet. Fur- 
thermore, the domain-labels can directly be used in in- 
formation retrieval (also in language-learning tools and 
dictionary publishing) to group concepts in a different 
way, based on scripts rather than classification. Domains 
can also be used to separate the generic from the do- 
main-specific vocabularies. This is important to control 
the ambiguity problem in Natural Language Processing. 
Finally, we save space by storing the language- 
independent information only once. 
The overall modular structure of the EuroWordNet 
database can then be summed up as follows: first, there 
are the language modules containing the conceptual 
lexicons of each language involved. Secondly, there is 
the Language Independent Module which comprises the 
ILl, the Domain Ontology and the Top-Concept Ontol- 
ogy. 
Language internal Relationships Language Module A Language Module A 
Interlingual relationships Language Module A ILl Module 
Language Independent Domain Internal Mod- Domain Module Domain Module 
Relationships ule Relationships 
Top-Concept Internal Top-Concept Module Top-Concept Module 
Module Relationships 
External Module Rela- Domain Module ILl Module 
tionships Top-Concept Module 
Table 1: Main categories of relationships 
Three different types of relationships are necessary in 
this architecture, summarized in the table 1. The rela- 
tionships operate upon five different types of data enti- 
ties: Word-Meanings, Instances, ILl records, Domains 
and Top-Concepts. The Word-Meanings are senses with 
denotational meanings (man) while the Instances are 
senses with referential meanings (John Smith). 
Figure 2 gives a simplified overview of how the dif- 
ferent modules are interconnected. In the middle the ILl 
is given in the form of a list of ILl-records: "animal", 
"mammal", ... "mane", "Bob", with relations to the lan- 
guage-modules, the domains, and the top-concepts. Two 
examples of inter-linked domains (D) and top-concepts 
(TC) are given above the ILl-records. The boxes with 
language-names (Spanish, English, Dutch, Italian and 
WNI.5) represent the Language Modules and are cen- 
tered around the ILI. For space limitations, we only 
show a more detailed box for the Spanish module. In this 
box we see examples of hyponymy and meronymy rela- 
tions between Spanish word-meanings and some of the 
equivalence-relations with the ILl-records. The full list 
of relations distinguished, its characteristics and assign- 
ment tests, as well as the structures of the different rec- 
ords can be found in the EuroWordNet deliverables 
D005, D006, D007 (available at: 
http://www.let.uva.nl/~ewn). 
EWN: Architecture Overview 
Language dependent object 
Language independent object 
Language Independent 
....... ' Relationships 
---~ Interlingual Relationships 
Language Internal 
Relationships 
Spanish \[ 
ILI 
Meaning 
~3 Instance 
ILI I ILI record 
TC I Top-Concept 
D I Domain 
II. D i 
The language dependent objects are connected with strings that are words.| 
The language independent objects are connected with strings that are labels. \[ 
Figure 2 
Next to the language-internal relations there are also 
six different types of inter-lingual relations. The most 
straight-forward relation is EQ_SYNONYM which 
applies to meanings which are directly equivalent to 
some ILl-record. In addition there are relations for 
complex-equivalent relations, among which the most 
important are: 
• EQ NEAR SYNONYM when a meaning matches 
multiple ILl-records simultaneously, 
• HAS_EQ_HYPERONYM when a meaning is 
more specific than any available ILl-record: e.g. 
Dutch hoofd only refers to human head and kop 
only refers to animal head, while English has 
head for both. 
• HAS_EQ_HYPONYM when a meaning can only 
be linked to more specific ILl-records: e.g. Span- 
ish dedo which can beused to refer to bothfinger 
and toe. 
The complex-equivalence relations are needed to help 
the relation assignment during the development proc- 
ess when there is a lexical gap in one language or 
when meanings do not exactly fit. 
As mentioned above, the ILl should be the super-set 
of all concepts occurring in the separate wordnets. The 
main reasons for this are: 
• it should be possible to link equivalent non- 
English meanings (e.g. Italian-Spanish) to the 
same ILl-record even when there is no English or 
WordNet equivalent. 
• it should be possible to store domain-labels for 
non-English meanings, e.g: all Spanish bull- 
fightmg terms should be linked to ILl-records with 
the domain-label bull-fighting. 
Initially, the ILl will only contain all WordNetl.5 
synsets but eventually it will be updated with lan- 
guage-specific concepts using a specific update policy: 
* a site that cannot find a proper equivalent among 
the available ILI-concepts will link the meaning to 
another ILl-record using a so-called complex- 
equivalence relation and will generate a potential 
new ILl-record (see table 2). 
• after a building-phase all potentially-new ILl- 
records are collected and verified for overlap by 
one site. 
• a proposal for updating the ILI is distributed to all 
sites and has to be verified. 
• the ILI is updated and all sites have to reconsider 
the equivalence relations for all meanings that can 
potentially be linked to the new ILl-records. 
3. Mismatches and language-specific 
semantic configurations 
Within the EuroWordNet database, the wordnets can 
be compared with respect to the language-internal 
relations (their lexical semantic configuration) and in 
terms of their equivalence relations. The following 
general situations can then occur (Vossen 1996). 
1. a set of word-meanings across languages have a 
simple-equivalence relation and they have parallel 
language-internal semantic relations. 
2. a set of word-meanings across languages have a 
simple-equivalence relation but they have diverg- 
ing language-internal semantic relations. 
3. a set of word-meanings across languages have 
complex-equivalence relations but they have par- 
allel language-internal semantic relations. 
4. a set of word-meanings across languages have 
complex-equivalence relation and they have di- 
verging language-internal semantic relations. 
\[ Dutch hoofd human head 
\[ Dutch kop animal head 
I Spanish dedo finger or toe 
I Spanish dedo finger or toe 
i i i 
, . , a 3r~,l-.J , , ., . 
HAS_EQ_HYPERONYM 
HAS_EQ_HYPERONYM 
HAS_EQ_HYPONYM 
HAS EQ,,HYPONYM 
Table 2: Complex-equivalence relations for mismatching meanings. 
head 
head 
finger 
toe 
Spares, A ILl ~ Enghsh(WNl5) \] 
\[_dedo-I ~qr"~._ ,ll( Fmger-a ~ ~.i I 
\[Extremlty-aJ ~Abodllyappendage I \[ Head-a l~artofbody I 
(Digit-C, dactyl-hi ~ finger-like part of i Head-b \] ~art of a human  ortehrato  I \[ 
} ) arto,,'nd ! Hoad-o I I 
I Toe-a } \]Part of foot I \[ Hyponym | .... 
\[Body part I I I equivalent | ) \[ 
Hyperonym equivalent 
Synonym equivalent 
Figure 3. 
Figure 31 gives some examples of the different mis- 
matches. Here we see that head-1 represents an inter- 
mediate level between human-head-1 and external- 
body part-1 in WordNetl.5 which is missing between 
their Dutch equivalent lichaamsdeel-1 and hoofd-1. 
While the equivalence relations match, the hyponymy- 
structure does not (situation 2 above). Furthermore, 
kop-1 does not match any synset in WordNet1.5. In the 
Spanish-English example we see on the other hand 
that ap6ndice-4 and dedo-1 have complex equivalence 
relations which are not incompatible with the structure 
of the language-internal relations in the Spanish word- 
net and in WordNetl.5 (situation 4 above). 
In general we can state that situation (1) is the ideal 
case. In the case of (4), it may still be that the word- 
nets exhibit language-specific differences which have 
lead to similar differences in the equivalence relations. 
Situation (2) may indicate a mistake or it may indicate 
that equivalent meanings have been encoded in an 
alternative way in terms of the language-internal rela- 
tions. Situation (3) may also indicate a mistake or it 
may be the case that the meanings are non-equivalent 
and therefore show different language-internal con- 
figurations. 
1 Obviously, the correspondence between WordNet and the 
ILl is very high, because it is bruit from it. Only m later 
stages of development, new ILl records occur 
4. Comparing the wordnets via the 
multilingual index 
The EuroWordNet database is developed in tandem 
with the Novell ConceptNet toolkit (Dlez-Orzas et al 
1995). This toolkit makes it possible to directly edit 
and add relations in the wordnets. It is also possible to 
formulate complex queries in which any piece of in- 
formation is combined. Furthermore, the ConceptNet 
toolkit makes it possible to visualize the semantic 
relations as a tree-structure which can directly be ed- 
ited. These trees can be expanded and shrunk by 
clicking on word-meanings and by specifying so- 
called filters indicating the kind and depth of relations 
that need to be shown. 
However, to get to grips with the multi-linguality of 
the database we have developed a specific interface to 
deal with the different matching problems. The multi- 
lingual interface has the following objectives: 
• it should offer new or better equivalence relations 
for a set of word-meanings 
• it should offer better or alternative language- 
internal configurations for a set of word-meanings 
• it should highlight ill-formed configurations 
• it should highlight ill-formed equivalence rela- 
tions 
,~. *ab.~ £1e:h o£ n.u:tm~tl~ (xneludxnc 
\[\]¢~:, has hl, lpezc~y~. 
\[\]~ 'vzece=. Z voeaxng 2 
ee~waaz 1 voedse 1 1 
~.¢::, ha~ :aezo :~adeo£ 
~ vleeJ I 
~ ce lwee£se 1 1 weegse 1 
gE~ersw~zex~ 1 
i eve=s=x ~a~ I en 1 
Figure 4. 
For visualising these aspects we designed an interface 
in which two wordnets can be aligned (see Cuypers 
and Adriaens 1997 for further details). In the screen- 
dump of the interface (figure 4) we see a fragment of 
the Dutch wordnet in the left box and a fragment of 
the Spanish wordnet in the right box. 2 The dark 
squares represent the meanings (WMs) m the lan- 
guages which are interconnected by lines labeled with 
the relation type that holds: has_hyperonym, 
has mero_madeof. Each meaning is followed by the 
synset ( as a list of variants with a sense-number) and 
on the next lines by the ILI-records to which it is 
linked (if any). These ILI-records are represented by 
their gloss (here all taken from WordNetl.5) and the 
kind of equivalence relation is indicated by a preced- 
ing icon, = for EQ_SYNONYM and ~ for 
EQ NEAR SYNONYM. By displaying the wordnets 
adjacently and by specifying the ILl-records sepa- 
rately for each synset in each tree the matching of the 
ILI-records can be indicated by drawing lines between 
the same ILI-records. When comparing wordnets one 
specific language can be taken as a starting point. This 
language will be the Source Language (SL). The SL is 
compared with one or more other languages which will 
be called the Reference Languages (RLs). 
There are then two general ways in which the 
aligned wordnets can be accessed: 
• given a (set of) WM(s) in a source wordnet with 
their corresponding ILIR(s), generate the same 
2 Only part of the available reformation is shown in this 
screen-dump. 
\[~ laa5 hTpe:~'FA 
_-- tha £ood end d:xnk tl:,.~ ~: 
_-- a souzce o~ no,.~=z=h=0a~ " 
\[\]Q 
\[\]1:! 
\[\]1:! 
ILIRs in the adjacent wordnet box with the corre- 
sponding WMs in the reference wordnet. 
given two comparable wordnet structures visualise 
the matching of the ILIRs: i.e. draw the lines be- 
tween the ILl-records that are the same. 
In the first option, a WM is first 'translated' into the 
second wordnet box, yielding a parallel twin-structure 
of ILI-records. Next the language-specific configura- 
tion of the Reference-wordnet can be generated 
(bottom-up). This gives you the semantic structuring 
of a particular set of WMs according to another word- 
net as compared to the Source-wordnet. 
In the second option the structures of both the Ref- 
erence and the Source wordnet are compatible and the 
inter-lingual relations are compared relative to this 
structure. Each set of ILI-records represents the most 
direct matching of a fragment of a wordnet from the 
available fund of ILI-records, regardless of the 
matching of the other wordnet. The equivalence rela- 
tions of these compatible fragments can then directly 
be compared. Loose-ends at either site of the ILl- 
records can be used to detect possible ILIR-records 
that have not been considered as translations in one 
wordnet but have been used in another wordnet. Dif- 
ferences in the kind of equivalence relations of WMs 
with compatible structure are suspect. Obviously, a 
comparison in this way only makes sense if the se- 
mantic-scope of the language internal relations is more 
or less the same. 
Both these options are illustrated in the above 
screen-dump. For example, the Dutch vleeswaren:l 
(meat-products) has an EQ_SYNONYM relation with 
meat.2 (= the flesh of animals ...), where the sense 
numbers do not necessarily correspond with Word- 
Netl.5 numbers, and a HAS_HYPERONYM relation 
to the synset voedsel:l. The latter is in its turn linked 
to the ILI-synset food:l(=any substance that can be 
metabolized...). We then copied the ILl-record meat 2 
into the Spanish wordnet yielding carne 1 as the syn- 
set linked to it. By expanding the hyperonymy- 
relations for carne'l we see that the Spanish wordnet 
gives three hyperonyms: tejido'3 (tissue: 1 = a part of 
an organism ..), comlda.'l (fare:l = the food and drink 
that are regularly consumed), and sustento 1 
(nourishment: 1 = a source of nourishment), all linked 
to ILl-records different from the Dutch case. When 
generating back the matching Dutch synsets for these 
hyperonyms it becomes clear that they are all present 
in this fragment, except for comida'l (fare:l) which 
does not yield a corresponding Dutch synset. First of 
all this comparison gives us new hyperonyms that can 
be considered and, secondly, it gives us a new poten- 
tial ILl-record fare:l for the Dutch wordnet. Further 
expanding the Dutch wordnet also shows that there is a 
closely-related concept vlees:l (the stuff where meat- 
products consist of) which matches both meat.2 and 
flesh:l(= the soft tissue of the body...). This concept 
thus partially matches the Spanish carne: 1. Since there 
is no matching Spanish concept related to flesh 1 the 
Dutch wordnet thus in its turn suggests a new potential 
ILI-record for the Spanish wordnet. In this way the 
aligned wordnets can be used to help each other and 
derive a more compatible and consistent structure. 
Given the fact that we allow for a large number of 
language-internal relations and six types of equiva- 
lence relations, it may be clear that the different com- 
binations of mismatches is exponential. Therefore we 
are differentiating the degree of compatibility of the 
different mismatches: some mismatches are more seri- 
ous than others. First of all, some relations in 
EuroWordNet have deliberately been defined to give 
somewhat more flexibility in assigning relations. In 
addition to the strict synonymy-relation which holds 
between synset-variants there is also the possibility to 
encode a NEAR SYNONYM relation between synsets 
which are close in meaning but cannot be substituted 
as easily as synset-members: e.g. machine, apparatus, 
tool. Despite the tests for each relation there are al- 
ways border-cases where intuitions will vary. There- 
fore it makes sense to allow for mismatches across 
wordnets where the same type of equivalence relation 
holds between a single synset in one language and 
several synsets with a NEARSYNONYM relation in 
another language. 
As we have seen above, a single WM may be linked 
to multiple ILI-records and a single ILl-record may be 
linked to multiple WMs. This allows for some con- 
strained flexibility. The former case is only allowed 
when another more-global relation 
EQ_NEAR_SYNONYM has been used (see above). In 
the reverse case, the same ILl-record is either linked to 
synsets which have a NEAR_SYNONYM relation 
among them (in which case they can be linked as 
EQ_SYNONYM or as EQ_NEAR_SYNONYM of the 
same ILl-record) or any other complex equivalence 
relation which parallels the relation between the WMs. 
Thus, two WMs which have a hyponymy-relation 
among them and which are linked to the same ILl- 
record should have equivalence-relations that parallel 
the hyponymy-relation: EQ_HAS_HYPERONYM and 
EQ_SYNONYM. A final type of flexibility is built in 
by distinguishing subtypes of relations. In addition to 
more specific meronymy-relations such as member- 
group, portion-substance there is an a-specific 
meronymy relation which is compatible with all the 
specific subtypes. 
In addition to more global or flexible relations, we 
also try explicitly define compatibility of configura- 
tions. First of all, differences in levels of generality 
are acceptable, although deeper hierarchies are pre- 
ferred. So if one wordnet links dog to ammal and an- 
other wordnet links it to mammal and only via the 
latter to animal first these structures are not considered 
as serious mismatches. Furthermore, since we allow 
for multiple hyperonyms it is possible that different 
hyperonyms may still both be valid. To make the 
compatibility of hyperonyms more explicit, the most 
frequent hyperonyms can be defined as allowable or 
non-allowable combinations. For example, a frequent 
combination such as act or result can be seen as in- 
compatible (and therefore have to be split into differ- 
ent synsets), whereas object or arnfact are very com- 
mon combinations. 
Finally, we have experienced that some relations 
tend to overlap for unclear cases. For example, intui- 
tions appear to vary on causation or hyponymy as the 
relation between Dutch pairs such as dzchttrekken 
(close by pulling) and dichtgaan (become closed). In 
these cases it is not clear whether we are dealing with 
different events in which one causes the other or one 
makes up the other. The events are fully co-extensive 
in time: there is no time point where one event takes 
place and the other event does not. This makes them 
less typical examples of cause-relations. By docu- 
menting such border-line cases we hope to achieve 
consensus about the ways in which they should be 
treated and the severity of the incompatibility. 
5. Conclusion 
The multilingual EuroWordNet database thus consists 
of separate language-internal modules, separate lan- 
guage-external modules and an inter-lingual module 
which has the following advantages: 
• it will be possible to use the database for multilin- 
gual retrieval. 
• the different wordnets can be compared and 
checked cross-linguistically which will make them 
more compatible. 
• language-dependent differences can be maintained 
in the individual wordnets. 
• language-independent information such as the 
domain-knowledge, the analytic top-concepts and 
information on instances can be stored only once 
and can be made available to all the language- 
specific modules via the inter-lingual relations. 
the database can be tailored to a user's needs by 
modifying the top-concepts, the domain labels or 
instances, (e.g. by adding semantic features) with- 
out having to know the separate languages or to 
access the language-specific wordnets. 
At the same time, the fact that the Inter-Lingual-Index 
or ILI is unstructured has the following major advan- 
tages: 
• complex multilingual relations only have to be 
considered site by site and there will be no need to 
communicate about concepts and relations from a 
many to many perspective. 
• future extensions of the database can take place 
without re-discussing the ILI structure. The ILl 
can then be seen as a fund of concepts which can 
be used in any way to establish a relation to the 
other wordnets. 
The structure of the database and the strategies for its 
implementation have been chosen out of pragmatic 
considerations. The architecture will allow maximum 
efficiency for simultaneous multilingual implementa- 
tion in more than one site, and will offer an empirical 
view on the problems related to the creation of an 
inter-lingua by aligning the wordnets, thus revealing 
mismatches between 'equivalent' semantic configura- 
tions. These mismatches may be due to: 
• a mistake in the eqmvalence-relations (inter- 
lingual links) 
• a mistake in the Language Internal Relations 
• a language-specific difference in lexicalization 
By using the cross language comparison and the tools 
described in section 4 a particular series of mismatches 
can provide criteria for selecting that part of the se- 
mantic network which needs inspection, and may give 
clues on how to unify diverging semantic configura- 
tions. This will constitute the first step towards gener- 
ating an interlingua on the basis of a set of aligned 
language-specific semantic networks. 

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formation retrieval, in: Proceedings of the Delos 
workshop on Cross-language Information Retrieval, 
March 5-7, 1997, Zurich, \[also available as 
EuroWordNet-working paper at Http: 
//www.let.uva.nl/~ewn\]. 
