2. The system as claimed in claim 1 , wherein one of the at least one input device receives the at least one sound signal, and the mode detection module uses a sound event detection module to detect whether the specific sound event is included in the at least one sound signal.
4. The system as claimed in claim 2 , wherein when the specific sound event is detected in the at least one sound signal, the sound event detection module outputs the speech training mode; and when no specific sound event is detected in the at least one sound signal, the sound event detection module outputs the speech recognition mode.