The most fundamental division in English dialects is the rhotic/non-rhotic division. The mechanisms of historical /r/-loss sound change are not well understood, but studying a contemporary /r/-loss sound change in a rhotic variety of English can provide new insights. We know that /r/ weakening in contemporary Scottish English is a gesture-timing based phenomenon and that it is socially indexical, but we have no phonetic explanation for the predominance of weak /r/ variants in utterance-final position. Using a socially-stratified conversational ultrasound tongue imaging speech corpus, this study investigates the effects of boundary context, along with other linguistic and social factors such as syllable stress, following-consonant place and social class, on lingual gesture timing in /r/ and strength of rhoticity. Mixed-effects modelling identified that utterance-final context conditions greater anterior lingual gesture delay in /r/ and weaker-sounding /r/s, but only in working-class speech. Middle-class speech shows no anterior lingual gesture delay for /r/ in utterance-final position and /r/ is audibly strengthened in this position. It is unclear whether this divergence is due to variation in underlying tongue shape for /r/ in these social-class communities, or whether utterance-final position provides a key location for the performance of social class using salient variants of /r/.

中文翻译：

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最终发声位置中 /r/ 的延展和强化，自发言语中舌手势时序的超声舌成像研究

英语方言中最基本的划分是卷舌/非卷舌的划分。历史上/r/-loss 声音变化的机制尚不清楚，但研究当代英语中的/r/-loss 声音变化可以提供新的见解。我们知道当代苏格兰英语中的 /r/ 弱化是一种基于手势计时的现象，并且它具有社会索引性，但我们无法对弱 /r/ 变体在话语最终位置中的主导地位进行语音解释。本研究使用社会分层的会话超声舌成像语音语料库，研究了边界上下文以及其他语言和社会因素（例如音节重音、后续辅音位置和社会阶层）对 /r/ 和 中语言手势计时的影响。强直性。混合效应模型发现，最终话语语境会导致 /r/ 和声音较弱的 /r/s 中的前语言手势延迟更大，但仅限于工人阶级言语。中产阶级语音显示 /r/ 在话语最终位置没有前舌手势延迟，并且 /r/ 在该位置明显得到加强。目前尚不清楚这种差异是否是由于这些社会阶层社区中 /r/ 的基本舌形的变化所致，或者话语最终位置是否为使用 /r/ 的显着变体的社会阶层表现提供了关键位置。