This paper proposes an algorithm for assigning the syntactic categories of over, many uses of which are not used as prepositions. The algorithm, enriched for the semantic capacity from earlier studies, identifies four syntactic categories of over and eleven meanings of the prepositional uses. The ability of the algorithm was tested manually by using five hundred instances of over from British National Corpus. The results are encouraging, with over 95 percent of the instances being correctly classified. This study, while pointing to an ideal direction, will reveal many important points to consider in natural language processing.