Looking at the Documentation for AVSpeechSynthesizer, you need to call -[AVSpeechSynthesizer pauseSpeakingAtBoundary:]
to stop speaking, and, then -[AVSpeechSynthesizer continueSpeaking]
to continue speaking again afterwards.
You can choose to pause speaking right away (AVSpeechBoundaryImmediate
), or, at the end of the current word (AVSpeechBoundaryWord
).