摘要：This paper tries to find out what knowledge sources Iranian EFL learners used while trying to infer the meaning of unknown words in the context. It is also intended to find out whether the students' level of L2 proficiency would affect the pattern of their use of the knowledge sources, and if there is a relationship between students' lexical inferencing strategy and their sex. To conduct the study, forty Iranian EFL learners, studying English at the private language institute, were selected to participate in the experiment, and then, they were divided into low and high intermediate levels based on their scores on FCE test. Four short stories were given to them, each story in one class session. The participants were asked to read the story, underline the unknown words, guess the meaning of those unknown words, and then specify the knowledge sources that they used to guess the meaning of the unknown words. The results showed that there were some differences among the students at these two levels regarding the type of knowledge sources used and success in lexical inferencing.
