Investigations designed to eliminate ambiguities in the Andre and Kulhavy procedure and to investigate the effects of noun modifications and sentence voice in the category clustering of sentences were conducted. Two experiments were carried out; both employed a mixed factorial design and were prepared in dittoed booklets. The Ss were run in groups. Experiment 1 utilized students taking graduate or undergraduate educational psychology. Experiment 2 used introductory psychology students. It was found that modification of categorizable nouns reduces recall and that sentence voice failed to produce a significant difference in recall or clustering. It was also found that organization processes play some role in the learning and remembering of sentences. (Author/CK)