1. A speech translation apparatus comprising: an associated-information storage unit configured to store a name of associated information relating to speech and a display position of the associated information, in association with each other; an example storage unit configured to store a semantic class representing a semantic attribute of a word, an example in a source language including the word, and an example in a target language acquired by translating the example in the source language, in association with each other; a dictionary storage unit configured to store the name of the associated information and the semantic class of the name of the associated information, in association with each other; a display unit configured to acquire the display position of the associated information from the associated-information storage unit and to display the associated information at the acquired display position; a speech receiving unit configured to receive speech spoken in the source language; a recognizing unit configured to recognize the received speech to generate a source language character-string in the source language; a selection receiving unit configured to receive a selection of the associated information displayed at the acquired display position; an acquiring unit configured to acquire the name of the associated information corresponding to the display position of the associated information the selection of which is received, from the associated-information storage unit, and to acquire the semantic class corresponding to the acquired name of the associated information from the dictionary storage unit; and a translation unit configured to translate the source language character-string into the target language by defining a search range of a subset of examples in the target language narrowed to those examples stored in the example storage unit having the same semantic class as the acquired semantic class, and acquiring an example in the target language corresponding to the source language character-string and having the same semantic class as the acquired semantic class from the subset of examples.
1. A speech translation apparatus comprising: an associated-information storage unit configured to store a name of associated information relating to speech and a display position of the associated information, in association with each other; an example storage unit configured to store a semantic class representing a semantic attribute of a word, an example in a source language including the word, and an example in a target language acquired by translating the example in the source language, in association with each other; a dictionary storage unit configured to store the name of the associated information and the semantic class of the name of the associated information, in association with each other; a display unit configured to acquire the display position of the associated information from the associated-information storage unit and to display the associated information at the acquired display position; a speech receiving unit configured to receive speech spoken in the source language; a recognizing unit configured to recognize the received speech to generate a source language character-string in the source language; a selection receiving unit configured to receive a selection of the associated information displayed at the acquired display position; an acquiring unit configured to acquire the name of the associated information corresponding to the display position of the associated information the selection of which is received, from the associated-information storage unit, and to acquire the semantic class corresponding to the acquired name of the associated information from the dictionary storage unit; and a translation unit configured to translate the source language character-string into the target language by defining a search range of a subset of examples in the target language narrowed to those examples stored in the example storage unit having the same semantic class as the acquired semantic class, and acquiring an example in the target language corresponding to the source language character-string and having the same semantic class as the acquired semantic class from the subset of examples. 2. The apparatus according to claim 1 , wherein the recognizing unit recognizes the received speech to generate candidates of the source language character-string; the selection receiving unit receives a selection of a candidate from the candidates displayed at the acquired display position; and the translation unit translate the candidate into the target language by acquiring an example in the target language from the example storage unit, the example corresponding to the acquired semantic class and the selected candidate.