 A history of scoring poorly on an array of language aptitude tests taken at the appropriate time (MLAT-E for grades 3–6, PLAB for grades 7–12, MLAT for adults) can provide even stronger evidence for a language learning disability.Evidence can also come from comparing a poor past performance in foreign language courses with above-average performance in other courses unrelated to language learning.Language aptitude is one of the important factors that determined L2 later learners' ultimate achievement, but it has less effect on L2 early learners.