Assuming that linguistic specifications and information
planning contribute to different levels of prosodic organization
that cumulatively constitute output prosody, quantitative
analysis of respective contributions can be derived through
normalization procedures that remove levels of interactions
involved. The current study attempts to account for how L2
prosody departs from the L1 norm in the two levels mentioned
and whether an account can be offered. F0 patterns of word
English stress categories (primary, secondary and tertiary) and
emphases in controlled conditions (narrow-, broad- and nonfocus)
are compared using speech data from English L1 and
Mandarin L2 speakers. L1 speech exhibits similar F0 patterns
of binary high-low contrasts in both stress/non-stress as well
as focus/non-focus categories, suggesting comparable
planning are used to express phonological and information
planning. However, L2’s primary stress and emphasis
exhibited less degree of F0 high-low contrast, coupled with
reversed F0 patterns in both the secondary and tertiary
categories as well as non-emphases conditions. The results
demonstrate that being less sensitive to phonological
categories may also affect information planning in similar
ways. We believe the results explain how stress and focus
interact to cause L2 accent and unintelligibility, help
understand stress and focus composition of L1-and-L2
speech, ,and are readily applicable to CALL.