Pronunciation Lexicon Specification

The language is intended to be easy to use by developers while supporting the accurate specification of pronunciation information for international use.

Here is an example PLS document: which could be used to improve TTS as shown in the following SSML 1.0 document: but also to improve ASR in the following SRGS 1.0 grammar: For ASR systems it is common to rely on multiple pronunciations of the same word or phrase in order to cope with variations of pronunciation within a language.

Because these are representations that have the same meaning (as opposed to homophones), it is recommended that they be represented using a single element that contains multiple graphemes.

Although it is recommended that these words be represented using separate elements that are distinguished by different values of the role attribute (see Section 4.4 of PLS 1.0), if a pronunciation lexicon author does not want to distinguish between the two words they could simply be represented as alternative pronunciations within the same element.

Note that English contains numerous examples of noun-verb pairs that can be treated either as homographs or as alternative pronunciations, depending on author preference.