document v. 记录、记载\nsystematic 有系统的、有条理的\nerror analysis：\n1. document the errors in learning\n2.determine whether the errors are systematic\n3.explain what cause those errors\nerror analysis:\ndocument-determine-explain\nError analysis is a method used to document the errors that appear in learner language, determine whether those errors are systematic, and (if possible) explain what caused them. The fact that learners make errors and that these errors may be seen, evaluated, and classed to indicate something about the system working within the learner sparked a rise in error analysis research.