引入新课是课堂教学的第一步,是课堂教学的重要环节和必要环节.精彩的新课引入不但会引起学生的有效注意,引发学生的学习动机和兴趣,还能达到承前启后、建立知识联系的作用.如果在引入新课时,能够精心设计,就会使教学渐入佳境,为教学任务的完成奠定坚实的基础. The introduction of a new lesson is the first step in classroom teaching and is an important and essential part of classroom teaching.The introduction of a wonderful new lesson not only arouses the students ’effective attention, arouses students’ motivation and interest in learning, but also achieves the goal of building a knowledge link If the introduction of new classes, can be carefully designed, it will make teaching better and better, for the completion of teaching tasks to lay a solid foundation.