So-called "Particle Ellipsis"
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Naoko MARUYAMA, Minako HASHIMOTO, and Wakako KUWAHATA
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Tokyo Woman's Christian University<BR>
Suginami-ku, Tokyo 167, JAPAN<BR>
e-mail: maruyama@twcu.ac.jp
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In Japanese sentences, case particles such as 'ga' and 'wo' are
sometimes missing.  In this paper, we study so-called "particle
ellipsis" from the following three points of view: 1)the
determination of the case, 2)the function of the ellipsis, and 3)the
difference between spoken and written languages.
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{1) Determination of the case}
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There have been several attempts to supply the missing case
particles.  However, identifying the most natural case particle does
not necessarily mean the determination of the case for the omitted
particle.  In this paper, we try to build a process for identifying
the proper case of the constituent for which the case particle is
missing.
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We use 8,000 spoken sentences taken from 86 dialogs.  There are 582
occurrences of particle ellipsis whose head-word modifies a single
verb.  454 modify the verb immediately follows the case element,
while 128 of them have other elements in-between.  If the case
element modifies the immediately following verb, the omitted
particle is 'wo' for the most of the time.  More specifically, there
are 214 examples of omission of 'wo', 155 for 'ga', 80 for 'ni', 4
for 'de', and 1 for 'to.'
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When the valency pattern of the modified verb contains the 'wo'
case, and when the sentence does not have an element explicitly
signaled as the case 'wo,' it is most probable that the missing case
is 'wo.'  Next come cases that represent the destination of action,
such as 'ni' and 'he' (we can confirm this when the head noun has
the semantic feature 'locative').
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Other than these, 'ga' or 'ni,' whichever closer the last element in
the valency pattern of the modified verb, is most likely the missing
case.
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When the case element is distant from the predicate verb, the
omitted particle is 'ga' for the most of the time.  'ga' accounts
for 60 examples, 'wo' is 40, 'ni' is 13, 'de' is 3, and others are
12.  'Others' include cases that do not appear in valency patterns.
When a noun is not strongly related to a predicate, it has more
topical role and it is difficult to determine its case.
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{2) Function of the ellipsis}
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Sometimes particle ellipsis conveys more meaning than with
particles.  For example, case element without a particle may be
considered to signify a topical role in a Japanese sentence. We
discuss similarities and differences between the topical particle
'ha' and no mark. In particular, we study things that affect
topicality - for example, the position in a sentence, the
characteristics of the noun and the predicate, the function of the
sentence, the pragmatic factors, and the phonetic features.  We plan
to study the function of ellipsis for other particles next year.
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{3) Difference between spoken and written languages}
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Case particle omission is observable in written languages as well.
However, the usage and meaning may be somewhat different from spoken
languages.  A lot of studies have done on the written languages, but
we intend to compare the use of case particle ellipsis between
written and spoken languages.  This is another issue in our plan
next year.
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Keywords: particle ellipsis, determination of case, valency, topic