1. A speech recognition apparatus comprising: a processor configured: to recognize a user's speech using any one or any combination of any two or more of a pronunciation dictionary comprising primitive words, and a language model comprising primitive words, the primitive words being formed of deconstructed compound words; and to correct word spacing in a result of speech recognition based on a word-spacing model, wherein spaces interposed between primitive words of deconstructed compound words are adaptively removed from the result of speech recognition to reconstitute the compound words.