Лингвистикада сөйлем құрылымы: номинативтік-аккузативті үйлесім

Concept of sentence structure in linguistics

In linguistic typology, nominative–accusative alignment is a type of morphosyntactic alignment in which subjects of intransitive verbs are treated like subjects of transitive verbs, and are distinguished from objects of transitive verbs in basic clause constructions. Nominative–accusative alignment can be coded by case marking, verb agreement and/or word order. It has a wide global distribution and is the most common alignment system among the world's languages (including English). Languages with nominative–accusative alignment are commonly called nominative–accusative languages.

It is common for languages (such as Georgian and Hindustani) to have overlapping alignment systems, which exhibit both nominative–accusative and ergative–absolutive coding, a phenomenon called split ergativity. In fact, there are relatively few languages that exhibit only ergative–absolutive alignment (called pure ergativity) and tend to be isolated in certain regions of the world, such as the Caucasus, parts of North America and Mesoamerica, the Tibetan Plateau, and Australia. Such languages include Sumerian, Standard Tibetan, and Mayan.

Nominative–accusative alignment can manifest itself in visible ways, called coding properties. Often, these visible properties are morphological and the distinction will appear as a difference in the actual morphological form and spelling of the word, or as case particles (pieces of morphology) which will appear before or after the word.

Not all arguments are equally likely to exhibit overt case marking. In languages with nominative–accusative alignment, it is common to divide direct objects into two classes (with respect to overt case marking), a phenomenon called ‘differential object marking’ by Bossong (1985).

Alternatively, alignment can also manifest visibly through agreement on the verb. In the following example from Amharic, the verb can be head marked for S, A, and O. Both S in the intransitive clause and A in the transitive clause are marked by the same affix ( ə ‘3SG. M’), while O in the transitive clause is marked by a different affix ( w ‘3SG. M. O’).

One of the ways in which the production of a nominative–accusative case marking system can be explained is from an Optimality Theoretic perspective. Case marking is said to fulfill two functions, or constraints: an identifying function and a distinguishing function. The identifying function is exemplified when case morphology encodes (identifies) specific semantic, thematic, or pragmatic properties or information about the nominal argument. Accusative case in the position of the direct object, for example, can be a strong identifier of patienthood. The distinguishing function is used to distinguish between the core arguments, the subject and the object, of a transitive clause. Helen de Hoop and Andrej Malchukov explain the motivation and need for the distinguishing function in "Case marking strategies":
blockquote|When a two place predicate R(x,y) is used to describe an event involving two participants, usually an agent and a patient, it is of utmost importance to avoid ambiguity as to which noun phrase corresponds to the first argument x (the agent) and which to the second argument y (the patient). For this purpose, case can be used to mark one of the arguments. If one argument is case marked, this already suffices for the purpose of disambiguation. Thus, from the distinguishing perspective, there is no need to case mark both arguments. Neither would it be necessary to case mark the one and only argument of a one place (intransitive) predicate. Indeed, it has been argued that in many nominative–accusative case systems only the y is case marked (with accusative case) while the x remains morphologically unmarked. It is useful for languages to have a means of distinguishing between subjects and objects, and between arguments A, S, and O. This is helpful so that sentences like "Tom hit Fred" cannot be interpreted as "Fred hit Tom." Tripartite alignment systems accomplish this differentiation by coding S, A and O all differently. However, this is not structurally economical, and tripartite systems are comparatively rare, but to have all arguments marked the same makes the arguments too ambiguous. Alongside the principle of distinguishability seems to operate a principle of economy. It is more efficient to have as few cases as possible without compromising intelligibility. In this way the dual pressures of efficiency and economy have produced a system which patterns two kinds of arguments together a third separately. Both accusative and ergative systems use this kind of grouping to make meaning clearer.