A NEW VIEW ON THE PROCESS OF TRANSLATION 
John A. Bateman, Robert T. Kasper 
Information Sciences Institute 
University of Southern California 
4676 Admiralty Way, Suite 1001 
Marina del Rey, CA 90292 U.S.A. 
JSrg F. L. Schfitz, Erich H. Steiner 
Institut ffir Angewandte Informationsforschung 
An der Universit£t des Saarlandes 
Martin Luther Strafle 14 
D-6600 Saarbrficken, FRG. 
Abstract 
In this paper we describe a framework for research 
into translation that draws on a combination of two 
existing and independently constructed technologies: 
an analysis component developed for German by the 
EUROTRA-D (ET-D) group of IAI and the genera- 
tion component developed for English by the Penman 
group at ISI. We present some of the linguistic impli- 
cations of the research and the promise it bears for 
furthering understanding of the translation process. 
1 Introduction 
In this paper we describe a framework for research 
into translation that draws on a combination of two 
existing and independently constructed technologies: 
the analysis component developed for German by the 
EUROTRA-D (ET-D) group of IAI and the genera- 
tion component developed for English by the Penman 
group at ISI. We have described some of the motiva- 
tions for and the basic organisation of the combined 
framework in Steiner and Sch~tz (1988) and Bateman, 
Kasper, Schfitz, and Steiner (1989). Here we present 
in more detail some of the linguistic implications of 
the research and the promise it bears for furthering 
understanding of the translation process. 
Although developed separately and for quite dif- 
ferent reasons, there is a decisive link between the 
two components in that ideas from a single linguistic 
theory, systemic-functional linguistics (e.g. Halliday, 
1985) have been incorporated independently in both 
projects. A partial implementation of the grammat- 
ical stratum of organisation found in Systemic Func- 
tional Grammar (SFG) provides the core of Penman's 
linguistic capabilities (Mann and Matthiessen, 1985), 
whereas there is a strong input from SFG in the se- 
mantic interpretation of ET-D's dependency struc- 
tures (Steiner, Schmidt and Zelinsky-Wibbelt, 1988). 
It is therefore also one of the motivations of this co- 
operation to investigate the potential of SFG as a tool 
for transfer in machine translation MT, and in the 
wider context of systemic-functional linguistics also as 
a theoretical environment and as a formalism for ex- 
pressing semantics. This should be of interest to a 
wider audience within computational linguistics, espe- 
cially as SFG has recently been attracting an increas- 
ing amount of interest in the field (see, e.g.: Houghton 
and Isard, 1987; Kasper, 1988; Patten, 1988; Patten 
and Ritchie, 1987; Mellish, 1988; Paris and Bateman, 1989). 
2 The projects involved 
2.1 Eurotra-D Analysis Module 
The German analysis module of our proposed MT sys- 
tem is based on the Eurotra Engineering Framework 
(Bech and Nygaard, 1988) enhanced by a semantic 
component derived from systemic theory. 1 The gen- 
eral Eurdtra philosophy for translation is described 
elsewhere (Arnold et al., 1986, 1987). The essentials 
of the Eurotra-D approach are to be found in Steiner, 
Schmidt, and Zelinsky-Wibbelt (1988). The Eurotra 
system is a transfer-based multi-lingual MT-system. 
It is stratificational in the sense that analysis and syn- 
thesis proceed through two syntactic levels (configu- 
rational and functional) and one semantic level, called 
the Interface Structure (IS). These interface represen- 
tations are semantically interpreted dependency struc- 
tures; they are described in more detail in Section 3.3. 
Each level is defined by a level-specific grammar and 
a lexicon. The connection between adjacent levels is 
established with translator-rules which define a tree- 
to-tree mapping between level representations. The 
main operation involved in the mapping is unification, 
i.e. the unification between already built objects and 
rules. Transfer between two languages takes place as a 
translation between the interface level representations 
of the source language (SL) and the target language 
(TL). 
1Our co-operation is not restricted to the Eurotra Engi- 
neering Framework formalism; other versions use the CAT2 
formalism (Sharp, 1988; Sch~tz and Sharp 1988). 
- 282 - 
2.2 Penman Generation Module 
The English generation component of our proposed 
MT system is Penman (Mann, 1983). Penman has 
been designed to be a portable, reusable text gener- 
ation facility which can be embedded in many kinds 
of computational systems. The linguistic core of Pen- 
man is Nigel (Mann and Matthiessen, 1983), a large 
systemic-functional grammar of English based on the 
work of ttalliday (1985) with contributions made by 
several other systemic linguists. Nigel is a large net- 
work of interdependent points of minimal grammat- 
ical contrast, called systems. Each of these systems 
defines a collection of alternatives called grammatical 
features. The semantic interface of the Nigel grammar 
is defined by a set of inquiries that control choices of 
grammatical features by mediating the flow of infor- 
mation between the grammar and external sources of 
information. 
Penman also provides structure for some of these 
external sources of information, including a concep- 
tual hierarchy of relations and entities, called the upper 
model. The upper model is typically used to mediate 
between the organisation of knowledge found in an ap- 
plication domain and the kind of organisation that is 
most convenient for implementing the grammar's in- 
quiries. We have made crucial use of the upper model 
in constructing our combination of the two compo- 
nents. In effect, the upper model can often mediate 
between the results of the MT analysis, expressed in 
ET-D Interface Structures, and the input that must be 
specified for Penman, expressed in the Penman Sen- 
tence Plan Language (SPL) (Kasper, 1989). Each of 
these information sources, the upper model, the Pen- 
man SPL, and the ET-D Interface Structures will now 
be described in detail. 
3 Components of the 
German-English Interface 
3.1 Penman's Upper Model 
Perhaps the crucial task for text generation is to be 
able to control linguistic resources so as to make the 
generated text conform to what is to be expressed. 
In Penman this is the responsibility of the grammar's 
inquiry semantics. Furthermore, a large subset of Pen- 
man's inquiries are taxonomic. These relate particular 
instances of what is to be expressed to the categories 
of semantic organisation that the grammar's seman- 
tics requires. These categories, and the relationships 
among them, constitute the upper model. 
The upper model serves to organize the proposi- 
tional content that needs to be expressed in text; in 
systemic-functional linguistics, this range of meaning 
is called ideational. Many ideational.inquiries can be 
expressed in terms of the classifications of concepts 
that the upper model provides. These classifications 
form an inheritance hierarchy that organises concepts 
according to how they may be expressed in English. 
Thus, when an application domain for which Penman 
is to generate language connects its concepts to those 
of the upper model, a single inheritance hierarchy is 
formed from which the grammar's inquiries can de- 
termine information about how any particular domain 
concept may be expressed in English. We refer to this 
single inheritance hierarchy formed from the applica- 
tion domain model and the upper model as the com- 
bined model. Inquiries that need to determine whether 
an application domain model concept belongs to the 
class defined by some upper model concept can then 
rely on simple inheritance inferences. For example, 
this type of inference allows Penman to ascertain that 
a domain entity is a process, rather than an object, 
and so should be expressed as a verb rather than as 
a nominal phrase. Much finer distinctions are drawn 
by the actual upper model, which currently contains 
approximately 200 concepts. 
By virtue of their positions in the inheritance hierar- 
chy, entities in the combined model also inherit roles 
from their ancestors. These can serve to define, for 
example, the types of participants that processes may 
have, or the types of qualities that may be ascribed to 
particular objects. Both inheritance of class member- 
ship and of roles find significant use in the construc- 
tion and interpretation of expressions in the Penman 
interface notation SPL. 
3.2 Penman Interface Notation - 
SPL 
Penman accepts demands for text to be generated in 
the SPL notation. SPL expressions are lists of terms 
describing the types of entities and the particular fea- 
tures of those entities to be expressed in English. The 
types of SPL terms are interpreted with respect to 
the knowledge base of general conceptual categories 
defined in the upper model. When the concepts of 
Penman's upper model are instantiated by more spe- 
cific concepts from an application program's knowl- 
edge base (i.e. world knowledge specific to the do- 
main of the application), then application concepts 
can be used directly in the SPL expression. The fea- 
tures of SPL terms are either semantic relations to 
be expressed, drawn from the relations\]roles defined 
by the combined model or direct specifications of re- 
sponses to Penman's inquiries. This latter possibil- 
ity provides for the input of information from other 
sources of knowledge known to be necessary for con- 
trolling generation, e.g. text planning information and 
speaker-hearer models. These types of meaning fall 
outside the kind of taxonomic, 'ideational' meanings 
defined in the upper model and so require separate 
treatment. Currently we specify information of this 
type as direct responses to Penman's inquiries since 
the inquiries are not limited to ideational meanings. 
SPL representations as a whole are used as input spec- 
- 283 - 
(HI / g-associative 
:speech-act (spactl / assertion :polarity (polarityl / positive)) 
:speech-act-id (speechact / Speech-act 
:speaking-time-id 
(speakingtime / time 
:time-in-relation-to-speaking-time-id speakingtime 
:time-in-relation-id (speakingtime 
eventtime 
speakir~time) eventtime 
:precede-q (speakingtime eventtime) notprecedes)) 
:event-time (eventtime / time 
:precede-q (eventtime speakingtime) precedes) 
:g-attribuant 
(N2 / europa :name Europe) 
:g-associated 
(N3 / Rueckstand 
:identifiability-q notidentifiable 
:g-scope 
(N4 / Anwend~n 
:identifiability-q identifiable 
:g-affected 
(NS / Spitzentechnologie 
:singularity-q nonsingular 
:multiplicity-q multiple 
:quantity-ascription (ql / quantity 
:number-relativity-q relative 
:high-quantity- q high 
:diminished-q diminished)) 
:relations 
((ml / g-epithet 
:domain N4 
:range (AI / industrie11))))) 
:circumstantial-theme-q(S9 HI) contert 
: relations 
(($9 / seit 
: domain H1 
:range (N6 / Wiederaufbauphase 
: singularity-q singular 
:multiplicity-q unitary 
: identifiability-q identifiable 
: nach 
(N7 / Krieg 
: singularity-q singular 
: mult iplicity-q unitary 
: ident if iability-q identifiahle 
) 
)))) 
Figure 1: SPL representation used to generate Since the reconstruction phase after the war, Europe has had 
a trailing position in the industrial application of many high technologies. 
- 284- 
ificstions by Penman's inquiries and hence are able to 
drive sentence generation in a way that is fully respon- 
sive to required communicative goals. 
An example of an SPL specification for a sentence 
is shown in Figure 1. 2 In this expression we can see a 
collection of SPL variables (HI, N2, N3, N4... ) which 
have types drawn from concepts and relations of the 
combined model for English and German described in 
the next section; these types include g-associative, eu. 
tops, Rackstand and Anwenden. The semantic rela- 
tions to be expressed and direct inquiry responses are 
prefixed with a colon; e.g. :speech.act, :identifiability. 
q, and :g-affected- those ending with -q and .id denote 
Penman inquiries. 
3.3 Eurotra-D Interface Represen- 
tations 
The Eurotra-D interface representations (ET-D IS) 
are semantically interpreted dependency structures. 
They represent dependency relationships between con- 
stituents by structural embedding, and additional lin- 
guistic information in their feature structures, includ- 
ing semantic relations and semantic (lexical) features, 
such as time, diathesis, modality, mood, topic, fo- 
cus, determination and number. An example of an 
IS-representation is given in Figure 2. In this repre- 
sentation we can see at the topmost node the features 
s-TENSE and s_ASPECT which are used to compute 
the appropriate time information for the SPL expres- 
sion. The German simul/durative ('present') has to 
be expressed in English with a 'present perfect' con- 
struction. The feature nclass--proper is responsible for 
the fact that in the SPL expression we can simple use 
the keyword macro :name which indicates any proper- 
noun lexical item. The features d.is\]rame and argi, 
1 < i < 4, are used to determine the process type (g- 
associative) and its roles (g-attribuant, g-associated). 
The feature g.scope in the SPL representation is in- 
serted from the IS feature d_pform=in of the NP gov- 
erned by Anwendung. 
These features axe referring to categories of an 
upper model that we have constructed for German 
(UM~); the UMG is essentially a re-expression of the 
transitivity relations worked out in Fawcett (1987). 
:Just as for the Penman upper model for English, which 
we shall now label UME, the German upper model is 
not a representation of a particular sentence: it is a 
representation of concepts into which IS roles and role- 
configurations are mapped. The UMG concepts then 
2This specification shows the finest level of detail of 
grammar control that may be given in an SPL expression. 
In practise, when using SPL it is possible to abbreviate 
or to default commonly used combinations of inquiry re- 
sponses; thus, for example, it is possible to replace all of the 
:speech-act, :speech-act-id, and :e~ent-time features shown 
in Figure 1 with the more coarsely-grained, specification 
:speech-act ~sssrt :tense present-in-past For more details 
see Kasper (1989). 
also stand in inheritance relationships to each other. 
Furthermore, a concept in UM~ may have slots (roles) 
which can be filled by other concepts, of specified types 
(role restrictions). Roles of the German IS grammar 
are linked to concepts of UM~ through the specialize 
predicate. When an IS is expressed in an SPL rep- 
resentation, the roles (st features) of IS are mostly 
substituted by the corresponding UMG concepts. 
Roles as well as features of IS may also be mapped 
into inquiry responses during transfer into SPL, as 
described in Section 4.3. The fact that for the time 
being the UMG is almost isomorphic to a represen- 
tation of the predicate-argument part of the German 
IS grammar is more due to time constraints than to 
any far reaching claims about the mutual relationships 
between an IS and an Upper Model, although the na- 
ture of that relationship is interesting and is receiving 
study in its own right. 
4 The Nature of the Transla- 
tion Process 
It is important from a conceptual point of view to 
keep apart the three levels of representation involved 
here: ET-D IS, UM~, and a description of the Ger- 
man sentence in SPL. The basic form of the transla- 
tion process is to transfer ET-D IS representations into 
Penman SPL representations. As ET-D IS and Pen- 
man SPL representations are both feature-based de- 
pendency structures, the formal aspects of the transfer 
from ET-D IS into Penman SPL are not very compli- 
cated. Determining an appropriate mapping for the 
content of particular values within ET-D IS represen- 
tations is by far a more challenging aspect of this trans- 
lation process. 
The translation process is achieved by employing 
three principal levels of transfer, which are described 
in detail below. The product of this multi-level trans- 
fer is an SPL representation of the English transla- 
tion of the original German sentence, which may then 
drive generation by Penman as in any other applica- 
tion domain. The translation process as a whole is 
summarised in Figure 3. The general strategy of this 
translation process should also generalise to future ap- 
plications in a multi-lingual MT environment. 
4.1 Upper model transfer 
Preparatory to being able to transfer IS representa- 
tions into corresponding SPL expressions for German 
sentences, a mapping needs to be established between 
the categories of UMo and appropriate categories of 
Penman's English specific upper model (UME). As 
an initial approximation, and one which makes maxi- 
mal use of mechanisms already developed for driving 
Penman, we take the concepts of UMG as specialis. 
ing the concepts of UM~. This mapping only needs 
- 285 - 
isd : 
{¢at=s, s_TENSE-s imul, s_ASPECT--durat ire, stype-main, d_vf orm=fini~ e, d_diath=aet } 
{cat-v, vfeat-stat ,roleffigov ,nb=sing ,humarg2ffinonhum ,humargl=hu,., ers_frame=cOcl, d_moodlindicative, 
d_lu=haben, d_is_rno--r I, d_isframe=arg12, arg2=associat ed, argl=attr, abstrarg2=abstr, 
abstrargl-abstr} 
{cat--np, whfno, sr=attr, role=argl ,nb=sing, msdefs=msabs, index~9, hum~hum, d_gender=neut er , cs=no , 
argtypeffull, abstr=abstr} 
{cat=n, wh--no, role=gov, nform=full, nclass=proper, nbffising, humfhum, ere _frame=null, d_lu=europa, 
d_is_rno=r i, d_isframe=argO, d_gender--neuter, count--mass, abstr=abstr} 
{cat--np, gh=no, sr=assoc iated, ro le=arg2, nb=s ing, msdefsffiqns indef, index=22, hum--nonhum, dem=no, cs--no, 
argtype=fu11, abstr=abstr} 
{cat--n, eh=no, role=gov, nform=full, nclass=common, nb=sing, hum=nonhum, ere _frame=c4, d_pformargl=in, 
d_lu=rueckst and, d_is_rno--r i, d_is frame=arg 1, count=mass, abstr=abstr} 
{catffinp, sh--no ,role=argl ,nb=sing ,msdefs=msdef, index=20, hum=nonhum, d_pform=in ,d_gender=fem, 
dem--no, cs--no, argt ype--full, abstr=abstr} 
{cat =n, gh=no, role=gov, nf orm---f ull, nclass=common, nb=sing, hum--nonhum, ere_frame=c2, 
d_pf ormarg3=durch, d_pf ormarg2=auf, d_morphsrce=deverb, d_lu=angendung, d_is_rno--r I, 
d_isframe=arg123, d_gender=f era, count=mass, abstr=abstr} 
{cat=np, wh--no, role=argl, nb=plu, medefs=msabs, index = 17, hum=nonhum, d_gender=fem, cs--no, 
argtypeffull, abstr=abstr} 
{catffin, wh=no, role=gov, nform--full, nclass=common, nb=plu, hum--nonhum, ers _frameffinull, 
d_lu=spit z ent echnologie, d_is_rno=r i, d_isframe=argO, d_gender=f em, count=count, abstr=abstr} 
{cat=ap, role=mod, nb=plu, msdefs=msabs, d_gender=fem} 
{¢at=adj, role=gov ,nb=plu, ere_frame--null, d_lu--viel, d_isframe=argO, d_gender=f em, deg=base} 
{cat=ap, role=mod ,nb=sing ,msdefs=msdef, d_gender=fem} 
{cat=adj ,role=gov ,nb=sing, ere_frame--null, d_lu=indus~riell, d_isframe=argO, d_gender=f era, 
degfbase} 
~cat =pp ,role=rood, top=yes, index=8 } 
{c at=p, role=gov, ers_frame=comp, d_lu=seit, d_isframe~argl} 
{cat=np, .h=no ,role=argl ,nb=sing, msdef s---metier, index=7, humffinonhum, d_gender=f em, dem--no, cs=no, 
argtypeffull, abstr=abstr} 
{¢atffin, whffino ,rolefgov ,nf ormffull ,nclass=common, nbfs ing ,hum--nonhum, ere_frame--null, 
d_lu=wiederaufbauphase, d_is_rno=r I, d_isframe=argO, d_gender=f em, count=mass, abstr=abstr} 
{cat =pp ,rol efmod, index=5} 
{cat=p ,rolefgov, ers_framefcomp, d_luffinach, d_isframefargl} 
{ca~=np, gh--no, role=argl, nb=sing, msdef s--msdef, index=4, hum--nonhum, dem=no, cs--no, argt ype=full, 
abstrffiabstr} 
{¢atffin, whffino ,role=gov, nformffu11, nclassfcommon, nb=sing, hum--nonhum, ers_frameffinu11, 
d_lufkrieg, d_is_rno--r I, d_isframefargO, count=c ount, abstr=abstr} 
I~igure 2: ET-D IS representation for: Seit der Wiederaufbauphase nach dem Krieg hat Europa einen 
R~ckstand in der industriellen Anwendung vieler Spitzentechnologien. 
- 286 - 
3~.tence 
EUROTRA - D 
semantic 
features 
syntactic 
features 
Q 
umg concepts. 
+ relations 
inquiry 
responses 
PENMAN 
SPL 
grammatical 
features 
__English 
Sentence 
ANALYSIS MULTI-LEVEL TRANSFER GENERATION 
Figure 3: The translation process 
- 287 - 
to be defined once, it is then available for all IS rep- 
resentations that need to be transferred. Translation 
of UMa categories (and hence, indirectly, of the IS 
semantic features) subsequently takes the form of in- 
ferencing over the inheritance relationships in the com- 
bined UMc&UME model. This is the standard way 
in which the general grammatical resources of Penman 
are made responsive to knowledge from particular ap- 
plication domains. Here, the German upper model is 
simply being made to play the role of a Penman ap- 
pllcation domain. 
Let us give an example of this type of transfer. 
In the example sentence whose IS representation was 
shown in Figure 2, we have the prepositional phrase 
Seit der Wiederaufbauphase .... Seit as a German 
preposition in one of its readings is linked into UMo 
as a concept that specializes a more general relation 
'g-spatio-temporal' in UMG. The UMa 'g-spatio- 
temporal' is further linked, by the preparatory map- 
ping already defined between the English and German 
upper models, to a UME concept 'static-spatial' and 
this UME category guides the responses to Penman's 
inquiries to consider all the grammatical constructs 
and lexical items of English that Nigel has available 
for realizing this concept. In particular, one of the En- 
glish realizations may be the English preposition since, 
which is thus one candidate for an acceptable trans- 
lation. Because the prepositional phrase is a modifier 
of the main process (indicated by the role feature and 
the fact that the main process and the modifier are 
siblings in the IS representation) we have to use in 
SPL a ':relations' construct to state this dependence. 
In SPL this is a special keyword which is used for in- 
formation that does not determine a unique inquiry 
response without reference to other contextual infor- 
mation. 
Apart from the specific example given here, the 
translation through the UMa&UM~ combination 
opens the way to relatively free, but still acceptable 
translations, and thus provides the framework for dis- 
cussing the notion of an acceptable translation, as dif- 
ferent from, say, a simple paraphrase. Note, in par- 
ticulax, that syntactic category need not be preserved 
in this translation process, which is important for the 
translation of, say, relative clauses in German into NP 
or PP modifiers in English, translation of pre-modifiers 
of German into post.modifiers in English etc. - all of 
which are classical translation problems between these 
and other languages. 
"At present, lexical transfer is also largely handled 
as a side-effect of transfers of this type. 
4.2 Semantic feature transfer 
Semantic features of the ET-D IS representation may 
also be transferred into sets of Penman inquiry re- 
sponses. This type of transfer is used for seman- 
tic information of kinds not approI)riate for inclusion 
in an upper model, e.g., textual organisation infor- 
mation, non-hierarchical conceptual information and 
speech act information. Penman has a rich variety of 
inquiries dealing with such information and so makes 
available a large set of resources and capabilities for 
any system that requires English as output. 
Information of these kinds is notoriously difficult for 
the usual types of syntactic transfer strategies. De- 
terminer selection, and, in particular, correct trans- 
lation of the indefinite and definite articles are an- 
other case of this. For example, the IS semantic fea- 
tures representing determination are translated into 
the inquiry responses that are responsible for control- 
ling determiner selection in Nigel as follows: {def = 
yes & nb = sing} =¢. {:identifiability-q identifiable 
& :multiplicity-q unitary & :singularity-q singular}. 
Thus, the features expressing definiteness in IS are 
mapped into inquiry responses giving information 
about whether a given phrase is identifiable; those fea- 
tures expressing number are mapped into responses 
concerning whether the concept is to be expressed as 
a single entity or as several distinct entities. These are 
some of the semantic dimensions around which NigeI 
organises the selection of determiners and quantifiers 
in English (for a fuller account of Nigel's treatment, 
see: Bateman and Matthiessen, 1988; also, for an ac- 
count of the ET-D approach, see: Steiner, Winter and 
Zellnsky-Wibbelt, 1987). It is this level of informa- 
tion at which meaning is preserved in translation, and 
not the syntax:tic level of determiner selection; this is 
dearly shown by the fact that translation between lan- 
guages with and without articles is possible. 
Another area which is translated in this way in the 
present system is the area of time. Both the Euro- 
tra appr~ch to time (cf. van Eynde, 1988) and the 
Nigel approach (cL Matthiessen, 1984) grew out of a 
critical appraisal of the Reichenbachian framework, al- 
though they took quite different directions from there, 
with Mar~hiessen following essentially SFG lines. Still, 
enough common ground has been preserved in order to 
make a transfer of ET-D time features (i.e. semantic), 
rather than tense features (morpho-syntactic), an in- 
teresting and possible enterprise. Tenses encode com- 
plex relationships between time of speaking, reference 
time, and time of event, in interaction with Adver- 
biais in particular, and it is only with the help of a 
type of transfer that gives access to this level of de- 
tail that we can arrive at the English 'present perfect 
tense' as a translation of the German 'present' plus 
a time adverbial. For example, in Figure 1, we can 
see the inquiry responses under the features :speaking- 
time-id and :event.time that convey this information 
to Nigel. These are the results of interpreting the fea- 
tures s.TENSE and s-ASPECT in the IS representa- 
tion shown in Figure 2. While we are not claiming 
that a direct mapping of tenses into tenses in SL-TL 
transfer is necessarily impossible, it would seem con- 
siderably more complex and translationally implausi- 
ble than encoding the meaning expressed by tenses, as 
we have done here in terms of inquiry responses. 
- 288 - 
4.3 Morpho-syntactic transfer 
It is also possible for morpho-syntactic features of 
the ET-D IS representation to be directly translated 
into corresponding grammatical features of the Nigel 
grammar; e.g. ET-D active/passive to Nigel active- 
process/passive-process. This type of transfer is very 
close to the idea of IS =~ IS transfer in Eurotra, but 
is used sparingly in the present application. Most of 
the morpho-syntactic features present in the IS repre- 
sentations do not need to be used directly since the 
semantic features give sufficient and more appropriate 
information for translation. 
5 Perspectives for MT and 
Text Generation 
Combining the resources of the ET-D German analy- 
sis component with the Penman English generator has 
created an interesting research environment for asking 
questions about transfer strategies in MT. As is well 
known, the transfer process in an MT environment 
places complex requirements on both the linguistic 
theories involved and on the theories of translation. 
Perhaps the most refreshing aspect of the endeavour 
has been the new perspective which one gets on old 
problems, which suddenly seem to lose the air of hav- 
ing a range of often tried and well known, but essen- 
tially unsatisfactory solutions. 
One whole class of questions relates to what should 
be preserved in a translation process, as different from, 
say, processes of paraphrasing or summarising. One 
possible answer to this is that what needs to be pre- 
served at least is the truth value of sentences and their 
translations. While this may serve as a useful bottom 
line from which to start, it has long been recognised to 
be no more than that. Many researchers argue that we 
also need to preserve the essential features of thematic 
structure and information structure. For most pro- 
jects at this time, this problem is difficult to address 
because the linguistic models embodied in them do not 
foreground that type of information, ttowever, with 
ET-D's interest in topic and focus, and with Nigel's 
fairly comprehensive treatment of theme, there is a 
very immediate way of making these aspects of lin- 
guistic information an accessible part of the transla- 
tion process. In the translation pair represented by 
Figures 1 and 2, for example, we can see that the IS 
s~mantic feature top=yes indicating thematic promi- 
nence have been transferred into the inquiry response 
specification :circumstantial-theme-q(S9 H1) context. 
This calls for the grammar to prepose the constituent 
realising $9, i.e. the Since-clause, into sentence-initial 
thematic position, rather than letting it appear later 
in the sentence as it would when non-thematic. 
The function of predicate-argument structures, es- 
pecially in connection with semantic casls is another 
interesting research topic (as suggested by Somers 
(1986) which can be addressed in the present con- 
text, especially as the two components involved share 
their essential notions of predicate-argument struc- 
tures from systemic linguistics. 
Our first translations in this research environment 
are still sentence-based; however, in the longer term we 
will concentrate our research interests on issues con- 
cerning text structure. The Penman group intends to 
enhance the Penman environment to the interpersonal 
and textual metafunctions of SFG. Although these ex- 
tensions will be made primarily for text generation 
they should be of interest also for the design of a text- 
based MT-analysis. 
In summary, then, we have introduced the projects 
involved, and the structure of the German-Engllsh 
transfer mechanism, offering specific examples of the 
transfer process for some of the features present in the 
IS analysis. 
ACKNOWLEDGMENTS 
John Bateman and Robert Kasper were sponsored 
in part by United States AFOSR contract F49620-87- 
C-0005, and in part by United States DARPA con- 
tra~:t MDA903-87-C-641; the opinions in this report 
are solely those of the authors. 
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