Logic programming has lacked devices for forward reasoning in finding \nproofs. This limitation has been addressed by two recent approaches: tabled Prolog and \n sequential Prolog. In this paper, we focus on the latter approach.\nWe present sequential Prolog with two types of sequential goals: sequential conjunctive\ngoals and\n``lemma\'\' goals. A lemma goal serves as an intermediate goal to another goal.\nOur language is suitable for a number of applications including GIS.\nWe also consider how to integrate full tabling into our interpreter.