In a previously published work by Casenhisier and goldberg (2005), skewed input (a verb with high token frequency), consistent input (repeatedly providing pronouns in the subject and object slots of the construction), and order of frequent verbs (the position of the verb with high token frequency in the training sentences) facilitated construction learning and generalization in firsl language acquisition. Nakamura's article is a replication of Casenhiser and Goldberg with similar input manipulation but with second language learners. The authors wants to test if the hypothesis proposed by recent usage-based approaches to language aqcusition are valid also for adult second language learners. The results are quite divergent from Casenhiser and Goldberg's work, leading the author to hypotheisze that input frequency effects alone are not enough to adult second language acquisition.