Bilingual Subtitles for Second-Language Acquisition and Application to Engineering Education as Learning Pills

This paper introduces the concept of bilingual subtitles, a kind of captioning in which a pair of subtitles (in the mother tongue, L1, and second language, L2) is shown at the same time on the screen. The aim of dual subtitles is to help the final user in different learning processes, due to the fact that several capacities (listening, reading, and matching) are exercised at the same time by the learner while watching dual-captioned media. The contribution of this paper is threefold. First, it presents DualSub, an open source desktop tool aimed to create bilingual subtitles. Second, a descriptive study was designed and executed to evaluate the extent to which bilingual subtitles are perceived by final users in the incidental vocabulary knowledge of a second language. Third, an experimental case study in which dual subtitles were used in the engineering education arena was carried out. The results of these surveys confirm that bilingual subtitles are perceived as useful in the different dimensions of the incidental vocabulary learning process (form, meaning, use) and are also helpful when applied to the educational domain (deliberate learning). (C) 2017 Wiley Periodicals, Inc.