Abstract:
Previous studies (Prasithrathsint 1994, 1997) showed that when and why kaan- and khwaam- nominalizers emerged in Thai; however, there has been no diachronic research on how kaan- and khwaam- syntactically and semantically developed their grammatical functions as nominalizers. The present research aims to explore how kaan and khwaam lexical nouns developed to kaan- and khwaam- nominalizers through a diachronic approach. The analyses of syntactic and semantic developments of kaan and khwaam grammaticalization are based on prose writings in inscriptions and documents from Sukhothai period to present-day Thai. Syntactically, it is found that the usages of kaan and khwaam from Sukhothai period to present can be categorized into three groups: kaan and khwaam as single lexical nouns; as elements in compounds, and as nominalizers. When compared to their usages of each category, kaan and khwaam single lexical nouns behave the same as general nouns--modified by nominal modifiers, and functioning as arguments in all NP positions in a sentence. In a compound, both kaan and khwaam occur as an initial or final element of a compound, of which the other element is a noun or a verb. As a nominalizer, kaan- nominalizes both nouns and verbs (non-adjectival verbs, i.e., transitive, intransitive) whereas khwaam- nominalizes adjectival verbs. When a verbal base is nominalized by kaan- or khwaam- its NP subject is transposed from the nominative case in pre-verbal position to the genitive case in as the object of a genitive preposition 'of'. Semantically, the lexical meanings of both kaan and khwaam gradually vary in abstractness; nevertheless, their concrete meanings are apparently different from each others, e.g., kaan ceremony and khwaam lawsuit while their most abstract meaning matter, event is similar, which historically developed to their grammatical meaning as nominalizers. However, their meanings represented in compounds are rather more abstract and general (less concrete and specific) than those of their lexical forms, and vary according to the other elements they are compounded with. When functioning as a nominalizer, the NPs nominalized by kaan- denote dynamic situations or concepts while those by khwaam- render state, quality ones. Regarding the interrelation of the development of the usages of kaan and khwaam from Sukhothai to present and grammaticalization of their functions as nominalizers, kaan and khwaam lexical nouns tended to decrease gradually, while kaan- and khwaam- nominalizers rapidly increased since the Rama V-VI periods to present. Kaan and khwaam functioning as lexical nouns tended to appear solely (without nominal modifiers) less, while increasingly occurred with specific nominal modifiers, i.e., noun phrases (with kaan) and verb phrases (with kaan and khwaam). The increase in co-occurrences with noun-phrase and verb-phrase modifiers led the lexical meanings of kaan and khwaam to be bleached or generalized, depending on the meanings of noun-phrase or verb-phrase modifying kaan and khwaam. Fitted in specific contexts of [kaan][NP/VP] and [khwaam][VP], kaan and khwaam generalized or analogized from co-occurring with few members to various members of noun classes and verb classes. This structural generalization together with bleaching of lexical meanings of kaan and khwaam in the aforementioned contexts facilitated the structural reanalysis of kaan and khwaam lexical nouns to be kaan- and khwaam- nominalizers [kaan- NP/VP] and [khwaam- VP].