Contains research objectives and reports one two research projects.National Science Foundatio

Applegate, J. R.

Matthews, G. H.

Yngve, V. H.

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XX. MECHANICAL TRANSLATIONV. H. Yngve W. S. Cooper G. H. MatthewsJ. R. Applegate D. A. Dinneen A. B. PhillipsJ. S. Bross E. S. Klima Rosemarie StraeussniggElinor K. Charney K. C. Knowlton J. ViertelA. N. Chomsky D. Lieberman Ruth V. WardRESEARCH OBJECTIVESThe primary objective of this basic research program is to find out how languagescan be translated by machine. Secondary objectives are concerned with evaluating thefidelity which can be achieved with different approaches, the usefulness of the transla-tions for various purposes, and their respective costs. Another objective is to add tothe general knowledge of noncomputational uses of digital computing machinery and toa basic understanding of human communication.The Mechanical Translation group has always stressed a basic, long-range approachto translation. We are placing emphasis on completeness where completeness is pos-sible, and on an attempt to find out how to do a complete job where it is not now possible.We are not looking for short-cut methods that might yield partially adequate translationat an early date - an important goal pursued by other groups. Instead we are looking formethods that will be capable of yielding fully adequate results whenever they apply. Weare thus seeking definitive solutions that will constitute permanent advances in the fieldrather than ad hoc or temporary solutions that may eventually.have to be discardedbecause they are not compatible with improved systems.In order to write adequate translating routines, we need, among other things, anadequate and detailed knowledge of the languages in question - a knowledge of theirformal properties as codes and a knowledge of how they are used to communicate. Lin-guistic research on the structure of individual languages thus constitutes an importantpart of our effort. German and English are being given primary attention, but otherlanguages are also being studied. Each language is studied as an isolated system. Thetranslation relationship between languages is a separate question and is being givenseparate consideration.An important part of our objectives is to investigate the various questions raised inthe attempt to mechanize language operations. We feel that some of the problems ofmechanization can profitably be studied without reference to any particular language.There may be aspects of the manipulation of language that are essentially nonlinguistic.One of our aims continues to be the development and provision of adequate researchtools in the form of computer programs that will facilitate linguistic research by pro-viding the linguist with easy access to the machine. Thus far, we have developed amethod of searching large quantities of English or German text for examples of particu-lar constructions. In cooperation with the Computation Center, M. I. T., we have devel-oped and have nearly finished programming an automatic programming system thatprovides the linguist with a problem-oriented notation system for use in writing com-puter programs.Some work is also being carried out that has as its aim the investigation of thefeasibility of programming computers in English. This work is being carried out incooperation with the Solid-State and Molecular Theory Group of Massachusetts Instituteof Technology.V. H. YngveA. THE GERMAN NOUN PHRASEThe work on the description of the German noun phrase continues. It has beenextended to include the description of the semantic correlates of syntactic structures.This work is supported in part by National Science Foundation.183(XX. MECHANICAL TRANSLATION)This problem can be characterized as follows.The description of a specific structure can be presented in the form of an orderedset of rules, the application of which will permit the generation of the structure in ques-tion. At various points in the set of rules, a decision is made to apply one rule ratherthan another. This choice determines the selection of some of the later rules to beapplied, or it may determine that at a later point in the set of rules, more choices willhave to be made. The problem that is relevant for mechanical translation is: How canthe factors determining these choices be characterized? As an example, consider thefollowing case: With a noun stem as the head of the noun phrase, the adjectival modifiersmay occur in a post-nominal relative clause or as individual words in prenominal posi-tion between the article and the noun. These two structures are the results of the appli-cation of different sets of rules in the construction of the noun phrase, that is, the setsof rules are identical up to a certain point, after which they diverge. The question tobe answered is: What factors influence the choice of rules which in one case will placethe modifier in a clause, but in the other case place it before the noun?It should be possible to represent the factors affecting the choice of specific sets ofrules that are to be applied in such a way that given the representation, a correspondingset of rules can be automatically selected from the total set of rules for producing gram-matical structures; that is, the representation serves as a specifier for a given struc-ture. The converse is also possible; that is, given a specific structure, it should bepossible to determine, first, the set of rules applied to construct it, and second, thespecifier that represents this set of rules. Since the process of translation is conceivedas a three-step process: (a) analysis of a sentence in the source language to obtain asentence specifier, (b) conversion of the source language specifier to the target languagespecifier, and (c) construction of the sentence in the target language from the specifier,a solution to the problems mentioned is essential to the preparation of a translation pro-gram.Additional work on the manipulation of grammatical rules in human communicationis also being done. Investigation of the processes involved in converting utterances pro-duced by the application of one set of rules to those produced by the application of anotherset that differs by one or two rules, or in the order in which the rules are applied,will be useful in preparing programs for the conversion of sentence specifiers.J. R. ApplegateB. THE ERGATIVE RELATION IN HIDATSAThe Siouan languages have often been cited as languages that exhibit the ergativerelation. The ergative relation is said to exist in a language when the mark of the objectof transitive verbs is the same as the mark of the subject of intransitive verbs. This184(XX. MECHANICAL TRANSLATION)mark may be a case affix, an agreement morpheme, or merely a position in thesentence. In Siouan studies, this relation has usually been referred to as a dis-tinction between actors and goals, in which goals function as objects of transitiveverbs and subjects of most intransitive verbs, whereas actors function as subjectsof transitive verbs and of a relatively few intransitive verbs. Early investigatorshave often referred also to the substantially passive nature of the Siouan languages.I have been able to show that, in viewing the sentences of Hidatsa (a Siouan lan-guage) in the context of the whole grammar, rather than as isolated events, theergative relation is not a fundamental feature of Hidatsa, if it can be said to existat all.Hidatsa has two kinds of verb phrases which differ from each other in severalrespects, one of which is that they require their subjects to take different case mor-phemes. Thusmace A caha ika (= the man saw a stick)mia A niti (= the woman is hungry)macz G nlhi (= the man stood up)c ha G hisi (= the stick is red)where the first word of each sentence is the subject; A and G represent the case mor-phemes that are added to the subject, and are selected by the verb phrase of the sen-tence; and the rest of the sentence is the verb phrase.There is a transformation in Hidatsa that substitutes a constituent sentence for theobject noun of a matrix sentence on the condition that the verb of the matrix sentencebelong to a certain class.(i) X-N-Vd- Y -- X-S-Vd - Ywhere Vd represents that class of verbs that may take sentences as their objects.Thus, the two sentences: mace G nihi (= the man stood up) and mia A mace ika (= thewoman saw a man), in which mace (= man) in the second sentence is the object noun ofthe Vd-stem ik- (= see), can be transformed into mia A mace G nilhi ika (= the womansaw the man stand up). One of the several Vd-stems is the stem he (= use, cause).Thus, the sentences: mace A ni ika (= the man saw you) and naka A asi he (= the childused a spoon) can be transformed into ndka A mace A ni ik he (= the child caused theman to see you).The Vd-stem he is unique, in that transforms of (i) that contain it as the main verbstem, undergo another transformation. This transformation removes the stem he ifit follows one of a large class of verb stems, which normally require their subjects totake the G case.(ii) X- Vtr - he- Y -- X- Vtr -Ywhere Vtr represents that class of stems which requires the removal of a fol-lowing he. Thus, there are the sentences:185(XX. MECHANICAL TRANSLATION)mace A ni A niti he (= the man made you hungry)mace A ni G nuhi he (= the man made you stand up)maceA caha G hatha (= the man made the stick be broken/the man broke thestick)where the third sentence comes from (i) and (ii) applied to the sentences mace A cahahe (= the man used a stick) and caha G hatha (= the stick is broken).Consider the following sentences, of which the first and third are transforms of (i)and (ii) and the verb-stems hatha (= break) and kani (= ask for) are Vtr-stems:naka A caha G hatha (= the child broke the stick)c ha G hisi (= the stick is red)naka A mace G hiupa kani (= the child asked the man for a shoe)mace G hinami (= the man is sleeping).Note that the words that are translated as English objects in the first and third sentenceshave the same case morphemes as do the subjects of the second and fourth sentences.We have seen, however, that these so-called objects are, in Hidatsa, the subjects ofthe verbs, and the apparent subjects of the first and third sentences are actually thesubjects of the causitive element he, which was deleted by (ii). Thus, the ergative,in itself, is not a fundamental relation in Hidatsa, but rather an automatic result of afundamental distinction between two types of verb phrase and a general causitive con-struction. In Hidatsa, subjects are marked differentially by the kind of verb phrasethat follows them, and objects, which may occur in both types of verb phrases, aremarked the same, and only by position.G. H. Matthews186

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