一、重视导入,激发学生兴趣导入是一个新课、一个新单元或一个新段落的开端,具有酝酿学生听课情绪,集中学生注意力,创设教学情境的作用。导入的类型多种多样,要针对不同的内容设计不同的导言,目的是引起学生的注意,激起其求知欲。如讲到核酸的知识,学生在日常生活中很少有感性 First, pay attention to the introduction, to stimulate student interest is the beginning of a new class, a new unit or a new paragraph, with brewing students to listen to emotions, focus on student attention, create a teaching situation. The types of introduction are various, and different introductions should be designed for different contents in order to arouse the attention of students and arouse their curiosity. For example, when it comes to nucleic acid knowledge, students have little sensibility in their daily life.