School education is based on the verbal communication by teacher. Therefore, it is necessary to search for more effective verbal communication method in biology teaching. This study investigated: 1. The effects of variations in the kinetic structure on students` achievement and cognitive structure. 2. The effects of variations in the amount of information included in discourse unit(D.U.) on students` achievement and cognitive structure. 3. The difference of the effects of the kinetic structure and the amount of information between the sexes. First, as to the results of investigations on the effects of kinetic structure, the group with high structure lesson showed higher achievement than the group with low and this difference was statistically meaningful(F=24.803, p=0.0001). And according to the analysis of students` cognitive structure, the former group showed higher integration index(I) and differentiation index(D) than the latter. Second, as to the results of investigations on the effects of the amount of information, the group with a few information lesson showed higher achievement than the group with many, and this difference was also statistically meaningful(F=16.874, p=0.0001). And according to the analysis of students` cognitive structure, the former group showed higher articulation index(A) and differentiation index(D) than the latter. These results suggests that the kinetic structure and the amount of information included in D.U. of teachers` verbal communication might have some effects on learners` achievements and cognitive structure. Third, when the results were analyzed by sex, there was a difference between boys and girls, especially boys were more affected by communication method than girls. Based on these results, it is suggested that contiguous discourse units in teachers` verbal communication should hold a large proportion of their verbal elements in common and the length of each D.U. should be short as possible. And teachers should give special attention to verbal communication method in boys class.