Referential identification and resolution are considered the keys to help readers grasp the main idea of a text and solve lexical ambiguities. The goal of this study is to design a computer system for helping college students who learn English as a Foreign Language (EFL) develop mental maps of referential identification and resolution in reading. Four modules, "Natural Language Processing (NLP)", "User Interface", "Recording", and "Feedback Tool", are implemented in the system. Results of this study showed that the more-proficient EFL readers were able to identify and resolve most of the references to form a coherent mental map from different parts of a text. The less-proficient readers commonly resolved references by relying on grammatical rules instead of semantic contextual clues. They often referred references to incorrect objects. To overcome the difficulties in figuring out the relationship between two words, the less-proficient readers usually asked for more feedbacks. As students progressed in reading, they requested fewer feedbacks in the online system. Some recommendations for future studies are discussed. (Contains 6 tables and 12 figures.)