Complex sentence: A speech corpus (or spoken corpus) is a database of speech audio files and text transcriptions in a format that can be used to create acoustic models (which can then be used with a speech recognition engine).
Split into simpler sentences: A speech corpus (or spoken corpus) is a database of speech audio files and text transcriptions. In Speech technology, speech corpora are used, among other things, to create acoustic models (which can then be used with a speech recognition engine).