知识的掌握一般分为知识的理解、知识的巩固和知识的运用三个阶段。理解知识是知识掌握的首要环节，也是新授课的主要任务。就化学教学来说，理解一般指了解教材文字内容的含义，懂得化学符号、术语所表示的事物的性质、变化，认识文字所表述的化学现象、原理的特定意义等... The mastery of knowledge is generally divided into three stages: the understanding of knowledge, the consolidation of knowledge, and the use of knowledge. Understanding knowledge is the first step in mastering knowledge, and it is also the main task of new teaching. In terms of chemistry teaching, understanding generally means understanding the meaning of the textual content of a teaching material, understanding the nature, changes in the chemical symbol, the terminology represented by the term, understanding the chemical phenomenon expressed in the text, and the specific meaning of the principle...