Does prosody influence segments differently in Cantonese and Mandarin? A case study of the open vowel /a/

The interaction between segment and prosody has been receiving increasing attention. While speakers of European languages are found to hyper-articulate their speech to maintain the distinction between the focused and unfocused portions, little is known about focus effects on vowels in Chinese languages. This study investigated the potential interaction between prosodic focus and vowels and tested whether the effects of focus function differently in Cantonese and Mandarin, two closely related Chinese languages. In a focus production experiment, the target vowels were analysed on the duration, formants and distances. The results showed that prosodic focus influenced the open vowel /a/ differently in Cantonese and Mandarin. Although focus increased the vowel duration in both languages, the on-focus vowels were lengthened to a greater extent in Cantonese. The effect of focus was minimal on the vowel formants, especially in Cantonese. For the Euclidean distances between the vowels under broad focus and those under the remaining focus types, no difference was found, but Cantonese and Mandarin diverged in the directions in which each focus type moved away from broad focus. These results suggest that, while speakers of both languages hyper-articulate on-focus vowels, there are more differences than similarities between the two languages.