1. A method for providing speech output for a speech-enabled application, the method comprising: receiving from the speech-enabled application a text input comprising a text transcription of a desired speech output; identifying at least one first portion of at least one token of the text input that differs from at least one corresponding first portion of at least one other token of the text input, and at least one second portion of the at least one token that does not differ from at least one corresponding second portion of the at least one other token; assigning contrastive stress to the identified at least one first portion of the at least one token, but not to the identified at least one second portion of the at least one token; generating, using at least one computer system, an audio speech output corresponding to at least a portion of the text input, the audio speech output comprising at least one portion carrying contrastive stress corresponding to the at least one first portion of the at least one token of the text input, to contrast with at least one other portion of the audio speech output corresponding to the at least one corresponding first portion of the at least one other token of the text input; and providing the audio speech output for the speech-enabled application.