Developing and Evaluating an Adaptive Business English Self-Learning System for EFL Vocabulary Learning

This paper developed an adaptive Business English self- learning system for EFL vocabulary learning. The components of word reoccurrence and learner engagement have been built into the system where the amount of unknown word reexposure in various customized texts increases and vocabulary enhancement tasks are added to promote learner engagement with wanted words. To evaluate the system effectiveness on EFL vocabulary learning, the experimental group read system-screened texts with immediate and repeated contacts with individuals' unknown words and performed vocabulary tasks specific to those unknown words, while the control group read online texts without unknown word reoccurrence and vocabulary practice. After one semester, these two groups were measured by one online vocabulary test, and an online user satisfaction investigation was also administered to the experimental group. The study found that the experimental group reading customized texts to reexpose to previously encountered unknown words in different texts along with doing individualized vocabulary exercises performed significantly better in EFL vocabulary learning than the other group. It was also found that the system was appealing for the learners to show positive attitudes toward the use of the system. The study demonstrated that the constructed adaptive Business English self- learning system could effectively promote vocabulary growth.