let synthesizer = AVSpeechSynthesizer () let utterance = AVSpeechUtterance (string: "테스트" ) utterance. voice = AVSpeechSynthesisVoice (language: "ko-KR" ) utterance. rate = 0.5 utterance. pitchMultiplier = 0.8 // utterance.volume = 1 synthesizer. speak (utterance)