3. A speech recognizing apparatus according to claim 1 wherein the input speech has syllables and wherein the duration predicator predicates the duration data for each one of the recognition units of the input speech using the following equation: ##EQU17## where represents a predicated value of the duration data of an n-th syllable of the input speech; d(i) represents the duration data of an i-th syllable of the input speech; and w(i) represents a weighing value of the duration data of an i-th syllable of the input speech.
3. A speech recognizing apparatus according to claim 1 wherein the input speech has syllables and wherein the duration predicator predicates the duration data for each one of the recognition units of the input speech using the following equation: ##EQU17## where represents a predicated value of the duration data of an n-th syllable of the input speech; d(i) represents the duration data of an i-th syllable of the input speech; and w(i) represents a weighing value of the duration data of an i-th syllable of the input speech. 4. A speech recognizing apparatus according to claim 3 wherein the reference speech has syllable types and wherein the reference speech is divided into a plurality of smaller reference sections, each one of said plurality of smaller reference sections forming a reference recognition unit, the speech recognizing apparatus further comprises a reference speech duration storage buffer for storing average duration data representing an average duration of each one of the reference recognition units of the reference speech for each one of the syllable types, and wherein the duration predicator predicates the duration for each one of the recognition units of the input speech using the following equation: ##EQU18## where represents the predicated value of the duration data of the n-th syllable of the input speech; d(i) represents the duration of the i-the syllable of the input speech; w(i) represents the weighing value of the duration data of the i-th syllable of the input speech; k(n) represents the syllable type of the n-th syllable of the input speech; and dr(k(n), k(n-1), k(n-r)) represent an average duration data of k(n) when a syllable type of (n-r)-th to n-th syllable types are respectively k(n), k(n-1), . . . k(n-r)).