演示实验教学主要有三个重要环节：一是实验操作，这是教师要努力做好的工作；二是实验观察，这是建立在实验目的的前提下，学生主动获得实验事实的直接方法；三是分析现象，这是教与学共同参与，实现教学目的的有效途径。从中我们可以看出，在演示实验教学中，最重要的环... Demonstration experiment teaching mainly has three important links: First, the experimental operation, this is the work that the teacher must strive to do well; The second is the experimental observation, which is based on the premise of the purpose of the experiment, students directly obtain experimental facts directly; Analyze the phenomenon. This is an effective way to participate in teaching and learning and achieve the purpose of teaching. From which we can see that in the demonstration of experimental teaching, the most important ring...