This presentation describes the current development of a Computer Assisted Language Learning (CALL) program, "Zero Checker," which enhances Japanese learner's comprehension and writing skills of zero anaphora.
Zero anaphora or zero pronouns (henceforth zeros) are the referential noun phrases (NPs) that are not overtly expressed in Japanese sentences. When referential NPs are the arguments of a verb such as subject, direct-, or indirect-object NPs, English language requires these NPs to be overtly expressed. In contrast, Japanese language does not have the same requirement; these NPs can be omitted if they are recoverable from a given context or relevant knowledge.
The use of zeros is common in Japanese and this posits a challenge for Japanese language learners for their accurate comprehension and natural-sounding production of Japanese sentences with zeros. Some learners fail to understand a passage correctly because of the difficulty identifying zeros and/or their antecedents. Other learners produce unnatural-sounding Japanese due to overuse or underuse of zeros. Yet, very few textbooks provide explicit instructions or exercises to overcome these difficulties with zeros. To fill this gap, we created Zero Checker, an autonomous on-line learning aid for zeros-related difficulties.
Zero Checker employs Centering Theory (Grosz et al. 1983, 1995) as the backbone of its algorithm. The program analyzes and indicates places of zeros of any given Japanese passage and asks the learners to identify the antecedents of identified zeros. Learners choose an antecedent that is matched against a Zero Checker-chosen antecedent. This breakdown of the zeros-identification process helps learners to identify zeros and their antecedents. This program also evaluates learners' overuse/ underuse of zeros when writing Japanese. By identifying appropriate places for zeros in learnersŐ composition and advising on the appropriate use of zeros, Zero Checker helps to produce more natural-sounding Japanese.