1. An apparatus for recognizing, in units of monosyllables, speech which is produced by a speaker in accordance with a predetermined language system and which is input to said apparatus, comprising: (a) first memory means for storing reference vowel patterns which respectively represent first categories of a first number which are, in turn, obtained by classifying a group of known reference monosyllables in accordance with types of vowel characteristic phoneme of the language system, said first categories including independent categories corresponding to a contracted sound and a syllabic nasal sound in addition to categories corresponding to basic vowels; (b) second memory means for storing reference consonant patterns of a second number which respectively represent the group of reference monosyllables which are, in turn, classified in accordance with types of consonant characteristic phonemes of the language system; (c) first processing means for converting the input speech into electrical signals and for generating acoustic parameter data of the input speech in accordance with the electrical signals; (d) second processing means, connected to said first processing means, for performing segmentation for dividing the acoustic parameter data into monosyllabic acoustic parameter components corresponding to monosyllables of the input speech; and (e) third processing means, connected to said second processing means and said first and second memory means, for comparing each monosyllabic acoustic parameter component among the monosyllabic acoustic parameter components with the reference vowel and consonant patterns so as to perform monosyllable recognition in accordance with determination of which first category of the reference vowel patterns and which second category of the reference consonant patterns maximally resemble the each monosyllabic acoustic parameter component of the input speech.