1. A method of converting marked-up text into a synthesized stream, comprising: providing marked-up text to a processor-based system; converting the marked-up text into a text stream comprising a plurality of vocabulary items; retrieving a plurality audio segments corresponding to the plurality of vocabulary items; concatenating the plurality of audio segments to form a synthesized stream; and audibly outputting the synthesized stream; wherein the marked-up text comprises a normal text and a paralinguistic text; and wherein the normal text is differentiated from the paralinguistic text by using a grammar constraint.