17. The computer readable medium according to claim 15 , wherein the computer program when executed within the recognition system is further for causing the recognition system to perform: selecting a voice section having a node which can be said vocabulary word termination as a ending point in a language of input voice in said recognition hypothesis graph as a voice section which is connected with said hypothesis that reached the garbage section in said second voice recognition process.
15. A non-transitory computer readable medium storing a computer program executable within a recognition system and for recognizing keywords included in input voice, the computer program when executed within the recognition system causing the recognition system to perform: a first voice recognition process that recognize said input voice according to said first grammar based on said voice feature amount of said input voice; and a second voice recognition process that recognize said input voice according to said second grammar based on said voice feature amount of said input voice, wherein said first voice recognition process generates said recognition hypothesis graph which indicates said structure of hypothesis that is derived according to said first grammar together with said score associated with respective connections of said recognition means in, said second voice recognition process acquires said structure and said score of said garbage section of each hypothesis that is derived according to said second grammar from said recognition hypothesis graph, and selects no smaller than one voice section having a node which can connected with said hypothesis as a starting point in said recognition hypothesis graph and connecting said structure and said score of a selected voice section with said hypothesis as said structure and said score of said garbage section to said hypothesis reached to said garbage section in said second grammar.