3. Apparatus for recognizing a speech pattern as a string of predetermined reference words according to claim 2 further characterized in that said speech pattern starting frame restricting means comprises: means responsive to the time registration best corresponding signals of the preceding level for selecting the minimum preceding level best correspondence signal, and means responsive to the preceding level time registration best correspondence signals and said selected minimum best correspondence signal for selecting time registration speech pattern starting frames of the current level.
2. Apparatus for recognizing a speech pattern as a string of predetermined reference words according to claim 1 further characterized in that said time registering means comprises: means responsive to the time registration speech pattern endframes of the immediately preceding level for restricting the range of time registration starting frames for the current level, and means responsive to said time registration correspondence signals, and the time registration speech pattern endframe signals for storing the best correspondence signal for each time registration endframe, a signal representative of the best corresponding reference word for each endframe and a signal representative of the time registration speech pattern starting frame corresponding to the best reference word for each endframe.