The creative use of English idioms has led to heterogeneous idiom variants that are particularly problematic for L2 learners. Drawing on a cognitive linguistic perspective of idiom learning, this paper categorizes English idiom variants into four major types, and reports on an empirical study that investigated the effects of variation type and proficiency level on Chinese EFL learners＇ comprehension of English idiom variants. Targeting non-English major college students of basic and intermediate English levels, the study confirmed the influence of proficiency level on learners＇ comprehension and evaluation of the difficulty of idiom variants. Structural change in idioms was found to be the easiest type and idioms modified in terms of literal imagery were the most difficult in comprehension. These findings suggest that the dominant ＂rote memorization＂ tends to limit learners＇ choices of comprehension strategies to literal translation and L1 transfer. The learning environment unsupportive of cultivating L2 learners＇ analytical ability is held accountable for the generally low success rates in comprehension of idiom variants.
