A CALL System for Learning Preposition Usage John Lee author Donald Sturgeon author Mengqi Luo author 2016-08 text Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers) Katrin Erk editor Noah A Smith editor Association for Computational Linguistics Berlin, Germany conference publication lee-etal-2016-call 10.18653/v1/P16-1093 https://aclanthology.org/P16-1093/ 2016-08 984 993