变式练习是培养学生思维能力的有效措施之一.常用的变式方法有:因果互逆强化训练,条件不变结论延伸,变换条件举一反三,缺少条件追根求源,隐去结论猜想判断,开放问题进行探索,变换条件改头换面,现分类举例说明. Variant practice is one of the effective measures to train students’ thinking ability. Commonly used variant methods include: causal reciprocal intensification training, conditional invariant conclusion extension, transformation conditions by analogy, lack of conditional root-seeking source, implicit conclusion judgment conjecture, openness The problem is explored, the transformation conditions are changed and the classification is illustrated.