1. A computer implemented method comprises: receiving by a processor device a user-based selection of first portions of a document displayed in a user interface on a display device in communication with the processor device, with the document having plural passages at least one of which is pre-associated with a default voice that is pre-associated with a first voice model, and with the first portions including tags that are association indicators; generating by the processor device in response to the user selection, a first visual indicium over the user-based selection, and a second, different visual indicium over second, different portions of the document that are not pre-associated with the default voice and the pre-associated first voice model; causing by the processor device the document to be displayed on the display device according to the generated first visual indicium and the second visual indicium; receiving a user selection of an action to override the pre-associated default voice; and overwriting by the processor, the default voice of one or more passages corresponding to the first portions, with a second voice and a second, different voice model according to the tag association indicators.