1. A spoken word generation system for speech recognition, comprising: at least one input device that receives a plurality of input signals, wherein the plurality of input signals at least includes at least one sound signal; a mode detection module that detects the plurality of input signals, when a specific sound event is detected in the at least one sound signal or at least one control signal is included in the plurality of input signals, the mode detection module outputs a speech training mode; when no specific sound event is detected in the at least one sound signal and no control signal is included in the plurality of input signals, the mode detection module outputs a speech recognition mode; a speech training module that receives the speech training mode, performs a training process on the at least one sound signal and outputs a training result; and a speech recognition module that receives the speech recognition mode, performs a speech recognition process on the sound signal and outputs a recognition result, wherein the system uses the mode detection module and the speech training module to train at least one word model synonymous to at least one preset word by marking left and right boundaries of the specific sound event or the at least one control signal as to indicate the at least one preset word and at least one new word to be added synonymous to the at least one preset word inputted by at least one user and to establish a connection between the at least one word model and the at least one preset word for the speech recognition module, wherein a computer executes the functions of the above modules.