高中生物课有三次学生实验.由于实验操作较复杂,技术难度较大,稍不注意,即致失败.现根据课本上对前二个实验的目的要求,以及所介绍的材料用具和方法步骤,谈谈我们指导学生做好这二个实验的几点体会. The high school biology class has three student experiments. Due to the complexity of the experimental operation and technical difficulties, little attention is paid to the failure. According to the textbook’s purpose requirements for the first two experiments, as well as the materials and method steps introduced, Talk about our experience in guiding students in doing these two experiments.