We describe a method to semi-automatically generate incorrect choices, or distractors, for cloze (fill-in-the-blank) questions. We generated distractors aimed at revealing what type of misunderstanding a student was having. English as a Second Language learners answered a series of cloze questions that presented distractors generated by our method. We analyzed their answers in order to see how native languages influence the type of distractor that is chosen. With this preliminary study, we intend to further individualize the use of an intelligent tutoring system for vocabulary learning.