This study investigates English liquids |l| and |(inverted are)|) produced by 11 Japanese students at two times during their first and fourth years at a bilingual university in Tokyo (T1, T2). Five native English speakers from the same university serve as the control group. Each speaker read the same word list at T1 and T2. The word-initial CV portion of 50 words that contained liquids were subjected to auditory evaluation to determine if (1) the liquids were produced more accurately at T2 than at T1, and (2) to what extent the liquids, |l| and |(inverted are)|, were identifiable as |l| and |(inverted are)|, respectively, at T1 and T2. For question (1), paired comparison judgments made by ten naive, native speakers of American English were obtained. For question (2), forced-choice identification by three trained listeners were obtained. The presentation of the results will separate the identification and paired comparison judgments for |l| and |(inverted are)| as singletons, and for |l| and |(inverted are)| in clusters in contrastive and noncontrastive environments. The findings are discussed in light of current models dealing with adult acquisition of second language pronunciation.