We have investigated the grasp of some of the basic concepts of motion by students taking the introductory physics course in Mechanics at United Arab Emirates University (UAEU). We have developed a short research-based multiple-choice test where we were able to extract some information about the state of knowledge of the students. In general, the students were found to have poor understanding. We have analyzed the results of the test using a mathematical function, the concentration factor, which may expose some particularly naïve models of basic physics concepts among students and serve to identify particular patterns in the students' thinking. Based on the outcomes and on our own experience, we have pinpointed some possible factors for the students' low performance. We have also recommended several methods which might enhance the students' understanding of the basic physics concepts.