(The Application of Complex Dynamic Systems Theory (CDST) in Language Learning Histories (LLHs

The present researcher has understood that an obstacle to create a worthwhile learning and instructional environment is because of the fact that the features of a chaotic, natural environment are not taken into account. The general purpose of this study is to show that the core complexity characteristics, many language learning theories and parameters are present in language development through resorting to empirical evidence of LLHs, interviews and other data from triangulation. The final claim is that SLA ought to be regarded as a Complex Dynamic System, therefore, CDS theory and CDST approach are offered as candidates for overall theory and approach to SLA respectively. In order to support this claim, in a case, experiential study, excerpts from 45 English LLHs and 15 interviews were offered to characterize how learners describe their learning processes. Some suggestions are offered in order to enhance EFL learners’ language development and teachers’ awareness about the principles of CDST approach.