If you are interested, you can download an mqpmaster. Use this to open speech/speech2 (one in Chinese and one in English) in the data directory. Take the sentence you want to give to Sylvanas Windrunner for example. Open speech.mpq/speech2.mpq,, and under the branch of sound/creature/undead MasterDNPC (branch selection is on the left, similar to resource manager), there is an undead MasterDNPCFarewell02.wav (the selected file is on the right, similar to resource manager). Right-click and select Select. Ok. Double-clicking this file is to open the audition with audio playback software.

And so on.