Why we use dependency grammar

I . First, I would like to say why I do care E.~mmmr formalisms. The point is not only t h a % I was %ra.ined a s a student of linguist-i c s and %hat I always ha.re been interested in theor~l Lcal ling'uJ, stics, but in the present context a.]SO ) and main].~ ~ that natu:e&:[ ].angu a g e processing systems mostly a~'e too complex to be bui].t, modified, comp].emented, enriched.,., o , without a solid theoretical baekground~ As Prof.Nagao puts it, theory Js i m p o r t a n t and v a l u a b l e f o r t h e explanaJ;ion ~).nd u n d c r s t a . n d i n g ~ a. ] a n g u & g e processing me.-de]. ~heu].d be u n d e r s t a n d a b l e on t h e b a c h g r o u n d (,f a p o w e r f u l ] . i n g u i s t i c t h e o r y . On t h e o t h e r h a n d ~ :[ would lille I;o s t r e s s that i f l i n ~ g t l J l l t i e s w a n t s -to be n s e f u ] , a~l{] t o lllaqke safe i t s own p e r s p e e t : i v e s , t h e n i t h a s t o be u s e f u l f o r :l.l.ng!\igi~J_~ q en__q6~ineeri_q C. T h i e m e a n s f o r me tha t ; t h e t h e o r y has 9o bc n o t o .n l y a d e q u a t e , hut a l s o e c o n o m i c a l and m e r l u ] a r . The t},s]~ o f t h e t h e o r y i s t o o f f e r a r e ] . a t i vel:7 complete framework, which never captures all th.e detai].s in their specific and often exeept : i , ona]. e h a r a c % e r , bu~ whic}! , am ] ( a r e n J e n s e n n o t e s i n her p o i n t ( 7 ) ~ o [ ' f ( . ' r s a m a x i m a l c o v e r a g e , i . e . w h i c h ceYi t~ , i r t .q means necessary and suff: ' : i .eien% for } iand l in t< a ] ] . :]uch d e t a i ] s am :Far a s they ~w'e re ]ev ,qx~ t for ' t h e / ~ i v e n a p p , ] i c a t i o n f i e ] d , I n "tl~:i.s r e s p e c t , %he t h e c > r e t i c a ] f r a m e w o r k e~m be c o m p a r e d to a fi [ ;he rman" S net ~ which nee(I n()'~ be l l s ed ' w h o l e , i f t h i s i s no't; n e c e s s a r y f o r ~be g i v e n p o o l ; some of the m e s h e s may be l e f t u n u s e d :il~ t h e ]~eag or a s h o r e , 'but i n a l a r g e r p c o l they may be useful. The most important p e i n t is that the meshes a r e t h e r e , and we know w b e r e [ ; hey are and for w h a t purpose " they might be 'useful° 2o The f o r m a l i s m i s / t o t the o n l y i m p o r t ~ l n ~ i n g r e d i e n i ; of a.n NLP system, and it I s n o t interesting here for its own ~akeo :[% i s true that %he bottleneck of an NLP system Is in hanjling-the "dirty" exceptional cases, ra'ther "i;han the cases dlreet].y fitting into the main body of this or tha,% theory. As a ma-l;%er o f fact, using a n y theory, we have. %o . face such intricate but common examples as Kirschner's cases of target language amblguity (or vagueness) corresponding e.g. to that of F, nglish ,i.n_~[-forms , or the long but lexiea]ly bound sequences of nouns in termino].ogioal noun groups, or a procedure translating ].exieal items by modifying the productive affixes of int.ernational terms of (]reek and ],atin origin and other "emergency rules" ensuring that 6t leas% an approximate (at leatvt partially readable) output will be