3. The method according to claim 2 , wherein the rhythm feature is represented as a phrase boundary location of the input speech data.
3. The method according to claim 2 , wherein the rhythm feature is represented as a phrase boundary location of the input speech data. 5. The method according to claim 3 , wherein acquiring the rhythm feature comprises: acquiring input text data corresponding to the input speech data; aligning the input text data with the input speech data; and determining the phrase boundary location based on alignment of the input text data with the input speech data.