ABSTRACT
This chapter addresses the issues of error treatment and assessment in idiom learning. Teachers need to understand the sources and types of errors students make in order to render effective treatment. Students make errors in idiom learning for a variety of reasons, including negative L1 transfer and failure to understand the connotation of an idiom. Production errors, on the other hand, are much easier to identify, and they usually draw more attention from teachers in error treatment. Assessment is an indispensable part of any language instruction, and idiom teaching is no exception. Teachers need always to be informed about how successful their students are in grasping the idioms they are learning. In selecting assessment tools, teachers need to take into consideration students' variables such as age, learning style, and language proficiency level, because these variables may affect an assessment tool's appropriateness and effectiveness.
