通过自学让学生主动获取知识,是发展学生自主能力的重要途径。有效的预习,能明确学生学习新知识的目的性和针对性,可以提高学习的质量。良好预习习惯的形成将为课堂教学节约许多宝贵的时间,使得教师不必讲解 It is an important way to develop student’s autonomy through self-learning that students take the initiative to acquire knowledge. Effective preview, a clear understanding of the purpose of learning new knowledge and targeted, can improve the quality of learning. The formation of a good pre-habit will save many valuable lessons in classroom teaching, so teachers do not have to explain