What does the 'dots' rule refer to in phonetics?

The 'dots' rule in phonetics is specifically associated with sounds that can be sustained, particularly in relation to allophonic vowels. This means that the 'dots' annotation is applied to certain phonetic transcriptions to indicate the presence of sounds that can be prolonged or held in a speech context. For example, when transcribing, it reflects that the vowel might have a corresponding consonant sound that is capable of being sustained.

The rationale behind this is tied to how these sounds interact with vowels in spoken language, specifically the way certain consonants may take on a syllabic quality or serve as a vocalic element in the absence of a clear vowel sound. In this context, the focus on sustained sounds is fundamental to understanding prosodic features in speech and how they contribute to sound production and perception.

This understanding also illustrates why the other options do not accurately describe the 'dots' rule. The mention of consonants under option one does not capture the specific nature of sustained sounds implied by 'dots.' Option three focuses exclusively on diphthongs, overlooking the broader application of the 'dots' rule. Similarly, option four relates only to syllabic consonants, which is a narrower aspect than what the 'dots' rule covers concerning