A Quantitative Study On Parts Of Speech Of English Polyfunctional Words

Parts of speech indicating grammatical function of words are an indispensable part in languages and attract much attention from researchers.In English there exist some words carrying on more than one part of speech.In this thesis,the words with more than one part of speech are called polyfunctional words;the number of parts of speech to which a word belongs is named polyfunctionality.The present study investigates polyfunctional words in English on data extracted from the British National Corpus from the quantitative linguistics perspective.The parts of speech of polyfunctional words are studied in four aspects.Firstly,the polyfunctionality and rank-frequency distributions of parts of speech are analyzed.Waring and right truncated modified Zipf-Alekseev distributions are successfully fitted to the data respectively.Secondly,the total 86 part-of-speech patterns(i.e.the type of combination of parts of speech to which polyfunctional words belong.For instance,the word "book" belongs to noun and verb.Hence its part-of-speech pattern is(n,v))are illustrated and then polyfunctionality as well as rank-frequency distributions of patterns are analyzed.Binomial and negative hypergeometric distributions prove to capture the polyfunctionality and rank-frequency distributions respectively.Thirdly,the mechanism of polyfunctional phenomenon is discussed:the polyfunctional words in English are formed by diversifying in the dimension of part of speech without changing word forms.All the rank-frequency sequences of variants(for instance,the word "clean" belongs to adjective and verb;"last" belongs to adjective and adverb;"principal" belongs to adjective and noun,then the verb,adverb and noun are variants of adjective)of all parts of speech are successfully modelled by Popescu-Altmann function.Finally,polyfunctional proportions of all parts of speech are analyzed:article has the highest polyfunctional proportion while noun and adverb have the lowest.Except that the data of article cannot be captured by any model and those of verb are captured by Dacey-Poisson distribution,the polyfunctionality of each part of speech distributes according to Singh-Poisson distribution.Based on quantitative linguistics,the present study describes the dynamic distribution of parts of speech of polyfunctional words in English,supplementing the research results of qualitative researches by predecessors.