本节课内容的引入方式有很多种,如实际情境的引入、动手实践操作的引入、质疑引入等.由于学生在小学四年级的时候对直线、射线、线段已有了形象的认识,知道它们之间的区别,并且理解直线的重要性质是两点确定一条直线,因此,笔者在引入课题时直接采用复习引入法.先给出直线、射线、线段的三种图形,询问学生是否还有印象?接着追问学生有关于这三种“线”还记得哪些相关的内容?引导学生打开记忆的闸门,组织学生小组 There are many ways to introduce the content of this lesson, such as the introduction of the actual situation, the introduction of hands-on practice, the introduction of questioning, etc. Since students already know the images of lines, rays and segments in the fourth grade of primary school, , And understand the important nature of a straight line is the two points to determine a straight line, therefore, the author introduced the subject directly to review the introduction of law.First give the line, ray, line of the three graphics, asking whether the students still have the impression ? Then ask students about the three “line ” Remember what the relevant content? Guide students to open the memory of the gate, the organization of student groups