Abstract
This study investigated the relationship among word frequency, learner performance, and teacher intuition about difficult words. It was expected that gaining deeper insights into such relationship would demonstrate the frequency of words reflected on the difficulty of them. Firstly, by employing a vocabulary size test that takes learner confidence into account, 180 university learners' vocabulary size was measured. The results of the test confirmed that the scores corrected by the degree of confidence were more sensitive to frequency levels than the raw scores. Secondly, when the distribution of difficult words judged by teachers were investigated across frequency levels, the number of difficult words were in accordance with the frequency levels. Lastly, the relationship between learner performance in vocabulary size test and teacher intuition about word difficulty was investigated. As a result, a strong correlation was revealed. The result is interpreted to show that the teachers were in fact capable of predicting difficult words. Combining all the results together, this study confirmed a close relationship between the frequency of words and their difficulty.
