练是学习过程中一个不可缺少的环节,是对学的检验,对讲的印证,对已学知识的巩固,并为接受新知识奠定基础。学必有练。练是有计划与有目的的能动性活动。练有量,量的大小应适度,过大或过小都不利于学生学习积极性的发挥。要做到教书育人的有效结合,练习要精就成为必然要求。练习要精,不仅有量的规定性,而且更要注重质的规定性。精题能体现出从特殊到一般的道理。做题能悟出类似题的共性,为做类似题提供了解题思路和方法。学生自主做出类似题,就有成 Practice is an indispensable link in the learning process. It is a test of learning, a proof of intercommunication, a solidification of learned knowledge, and a foundation for accepting new knowledge. Learning must practice. Practice is a planned and purposeful activity. Practice, the amount of size should be appropriate, too large or too small are not conducive to the enthusiasm of students to play. To be an effective combination of teaching and educating people, practice must be refined to become an inevitable requirement. Practice to be refined, not only quantitative provisions, but also pay more attention to the quality of the provisions. Essay can reflect the special to the general truth. Do the title can understand the similarities of similarities, to provide similar questions to provide ideas and methods. Students make similar questions independently, there is success