The Role of Acoustic Parameters in Distinguishing Persian Simple Past and Present Perfect Tenses

This paper addressed the acoustic factors involved in distinguishing simple past and present perfect tenses in Persian. The pronunciation of Persian simple past and present perfect tenses in colloquial speech are the same segmentally but different in terms of the position of stress. In an experimental study, the pattern of distribution of some important prosodic parameters, including F0, intensity, and duration, was investigated in a speech corpus consisting of 24 sentences. Results suggested that none of the study parameters could differentiate simple past and present perfect tenses reliably and consistently. After normalizing F0 and computing the average pitch for all acoustic data per speaker, it was found that it is the value of F0 peaks and valleys in the target syllables that makes a fundamental distinction between simple past and present perfect. Results of statistical tests confirmed this finding, suggesting that the local F0 value is a reliable and consistent parameter that distinguishes simple past from present perfect in both the syntagmatic and paradigmatic axes.