The document discusses the characteristics of input in foreign language (FL) and second language (SL) settings. In FL natural settings, input is modified and contains ungrammaticalities. In FL instructional settings, traditional input focuses on rules and comes from the teacher, while communicative input is used for communication and learning rules. In SL natural settings, input is modified and "unlimited." In SL traditional instructional settings, input is structurally simplified and sequenced, and access is limited. In SL communicative settings, input is simplified and contains some errors and corrections.