Proceedings of the Annual Meeting of the Cognitive Science Society

New words were embedded in high- and low-constraint sentences and presented three times in a random order toadult learners of Chinese as a second language. The learners explained the meaning of each word in their native languages andtheir answers were scored by other native speakers. The overall accuracy was .47 with no effect of constraint or frequency.When the data were limited to those words the learners reported having no prior encounters with and those sentences theyreported comprehending, the accuracy was .45. The results demonstrated fast mapping of word learning in adult L2 learners butindicated that extended mapping was necessary to achieve ultimate attainment. The results are also consistent with Krashen’s(1982) “comprehensible input” and “i+1” hypothesis.