Journal Pre-proof Epistemic agency, a double-stimulation, and video-based learning: a formative intervention study in language teacher education Hongzhi Yang PII: S0346-251X(20)30761-2 DOI: https://doi.org/10.1016/j.system.2020.102401 Reference: SYS 102401 To appear in: System Received Date: 9 April 2020 Revised Date: 18 October 2020 Accepted Date: 29 October 2020 Please cite this article as: Yang, H., Epistemic agency, a double-stimulation, and video-based learning: a formative intervention study in language teacher education, System, https://doi.org/10.1016/ j.system.2020.102401. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Crown Copyright © 2020 Published by Elsevier Ltd. All rights reserved.