17. The apparatus as claimed in claim 12 , wherein the storage unit is configured to store a database of phonemes in the primary language, and the controller is configured to segment the voice input signal in a unit of phoneme, determine a similarity between at least one segmented phoneme and a word in the primary language by matching the at least one segmented phoneme with the database of the phonemes in the primary language, and identify that the at least one segmented phoneme having the determined similarity less than a preset threshold belongs to the segment of the voice input signal.
12. An apparatus that recognizes a voice input signal involving multiple languages, the apparatus comprising: a microphone configured to receive a voice input signal which is input by a user; a storage unit configured to store a voice recognition algorithm for a primary language and a voice recognition algorithm for a non-primary language; a controller configured to recognize the voice input signal by using the voice recognition algorithm for the primary language, identify a segment of the voice input signal, which is in the non- primary language, in the voice input signal based on the recognition for the primary language, determine a language of the segment of the voice input signal based on context information, and recognize the segment of the voice input signal by using a voice recognition algorithm for the determined language; and a display unit configured to output a recognition result of the voice input signal which is based on the recognition for the primary language and the recognition for the determined language.