A comparative study of native (L1) and Nonnative (L2) English speech strategy for discourse prosodic organization

English speech of L1 English and L1 Bengali speakers of the same discourse is analyzed by applying hierarchical discourse prosody framework HPG (Hierarchy of Prosodic Phrase Group) in order to find the between-and within-group similarities and differences in speech planning of L1 (native) and L2 (non-native) English speakers for prosodic organization at discourse level. The analysis reveals that the speech rate of L1 speakers is higher than speech rate of L2 speakers; L2 speakers contain more break boundary than that of the L1 speakers at every discourse prosodic level in the organization, which exhibit the fact that L2 speakers use more intermediate chunking units and larger scale planning units than that of L1 speakers. Between-group differences are also found through the analysis of phrase component at prosodic phrase level (PPh) and accent component at prosodic word level (PW). These findings can be attributed to L2 speakers' improper phrasing, improper word level prominence and ambiguous difference between content words and function words in discourse prosodic organization.