In daily conversations, overlaps can be placed at IU boundary. However, most of them
violate the sequential organization of talk and occur within an IU. The purpose of this study is to explore how the Chinese speakers initiate overlap at these two major sites. The results show that the interactive unction of the initiator’s utterance does not
determine the placement of overlap. The distribution of interactional and non-nteractional utterances, floor-taking and on-floor-taking utterances, as well as the arious kinds of non-interactional speech, is similar across the two overlap types. Two constraints were found at IU boundary. The first has to do with turn organization, in
that a boundary overlap tends to take place at the first speaker’s turn beginning due to its vulnerability. The second constraint is partly syntactic and partly prosodic, since the clause-completion point and/or the oundary prosodic cues might suggest turn completion,which is appropriate for the initiator to start a new turn. Finally, the main predicate is the syntactic site where the speaker inclines not to place an verlap, because it usually bears important information in the clause. This structural consideration is the only constraint for IU-internal overlaps.
Journal of Chinese Language and Computing, 14(2), 139-156