Difficulties with wh-questions in Czech TTS system

Abstract

The sentence intonation is very important for differentiation of sentence types (declarative sentences, questions, etc.), especially in languages without fixed word order. Thus, it is very important to deal with that also in text-to-speech systems. This paper concerns the problem of wh-question, where its intonation differs from the intonation of another basic question type – yes/no question. We discuss the possibility to use wh-questions (recorded during the speech corpus preparation) in speech synthesis. The inclusion and appropriate usage of these recordings is tested in a real text-to-speech system and evaluated by listening tests. Furthermore, we focus on the problem of the perception of wh-question by listeners, with the aim to reveal whether listeners really prefer phonologically correct (falling) intonation in this type of questions.