CASTLE: a Computer-Assisted Stress Teaching and Learning Environment for Learners of English as a Second Language

In this paper, we describe the principle and functionality of the Computer-Assisted Stress Teaching and Learning Environment (CASTLE) that we have proposed and developed to help learners of English as a Second Language (ESL) to learn stress patterns of English language. There are three modules in the CASTLE system. The first module, individualised speech learning material providing module, can provide learners individualised speech material that possesses their preferred voice features, e.g., gender, pitch and speech rate. The second module, perception assistance module, is intended to help learners correctly perceive English stress patterns, which can automatically exaggerate the differences between stressed and unstressed syllables in a teacher's voice. The third module, production assistance module, is developed to help learners to be aware of the rhythm of English language and provide them feedback in order to improve their production of stress patterns.