1. A computer-implemented method for enrolling a user in a speech recognition system, comprising: obtaining data representing a user's speech, the speech including multiple user utterances and generally corresponding to an enrollment text; analyzing acoustic content of data corresponding to a user utterance; determining, based on the analysis, whether the user utterance matches a portion of the enrollment text; and if the user utterance matches a portion of the enrollment text, using the acoustic content of the user utterance to update acoustic models corresponding to the portion of the enrollment text, wherein determining whether the user utterance matches a portion of the enrollment text comprises a determination that the user utterance matches when the user has skipped at least one word of the portion of the enrollment text.