This qualitative multiple-case study investigated the roles of indirect asynchronous electronic feedback and direct feedback on lexical errors (calques and collocations) produced by Thai undergraduate students. The study consisted of two phases: 1) a pilot study and 2) the main study. Data collection was carried out through text analysis, interviews, and observations. The pilot study was conducted with university students who shared more or less the same characteristics as those in the main study. More specifically, six typical cases were divided ...