17. The device of claim 16 , wherein the speech translation system is for: automatically using the first automatic speech recognition module when it is identified by the speech translation system that an input utterance is in the first language; and automatically using the second automatic speech recognition module when it is identified by the speech translation system that the input utterance is in the second language, without having the user input to the device who is speaking in a dialog between two speakers.
16. The device of claim 8 , wherein the speech translation system: further comprises: a second automatic speech recognition module for recognizing speech in the second language; and a second machine translation module for translating recognized speech in the second language to the first language: and is further configured to identify whether the utterance is in the first language or the second language.