This document discusses a study that investigated the opportunities and challenges of using social networking sites (SNSs) as learning environments for developing English writing skills among English as a foreign language (EFL) learners. The study examined 24 EFL learners who participated in a Facebook group for practicing English writing. The findings showed that participation and interaction increased over time as learners generated ideas, wrote paragraphs, and provided feedback to each other. However, the study also identified some challenges faced by learners in such online communities. The document provides background on theories of second language acquisition and communities of practice to frame the study.