Used three principal databases

The methods of investigation: The methods of description, the method of componential analysis, the method of contextual analysis, distributional method, the method of choosing hyphenated words among the compound words, the classifying method, the method of semantic analysis. Methodological basis of the research is Decrees of the President of the Republic of Uzbekistan about the development of languages, education and science, the national program on a professional training and also basic researches in the field of word formation and lexicology of the English language as Plag, I. 2003. Word-Formation in English. Cambridge, Adams, V. 2001. Complex Words in English. Harlow: Longman, Allen, M. R. 1978. Phonetic and morphological Investigations. PhD dissertation, University of Connecticut, Bauer, L. 1983. English Word-Formation. Cambridge: Cambridge University Press, Bauer, L. 2001. “Compounding”, Berlin, Bauer, L. 2008. “Dvandva”. Word Structure, Grimshaw, J. B. 2005. Words and Structure, Stanford, CA, Juhasz, B. J., Starr, M. S., Inhoff, A. W., & Placke, L. 2003. The effects of morphology on the processing of compound words: Evidence from naming, lexical decisions and eye fixations. British Journal of Psychology 1994, Levi, J. 1978. The Syntax and Semantics of Complex Nominals. New York: Academic Press, Lieber,R. 2008. “On the Lexical Semantics of English Compounds”. Talk given at the CompoNet Congress on Compounding 2008, University of Bologna, Marchand, H. 1969. The Categories and Types of Present-Day English Word-Formation. Munchen, Adams, V. 1973. An introduction to modern English word formation. London.
The scientific and practical importance of the research work. The practical importance of the work is that it enriches the scientific mental out look of the students on hyphenated words. Students will explore these areas through a particular method:

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  Historical development of English vocabulary;
  
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  Phonetic and morphological study: word formation;
  
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  Semantic study: word meaning and sense relations;
  
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  Word in context
  
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  lexical and phonetic and morphological change
  

The scientific-practical importance is that when the work is learned perfectly, the results can be used as the main source for the subject learning linguistics that is taught to the freshmen. Besides relying on this work, scientific methodological manuals can be created several creations have been done on the work. For instance, all the hyphenated words that exist in the English language have been noted to the shoots separately, so that more than thousands of hyphenated words have been written down. In the future all the hyphenated words that have been found out in the Explanatory dictionary, will be compared with theirs synonyms and the results will be noted.