该类型与常见的等积式 (浕ｂ =ｃｄ ,俗称标准型 )相比较为复杂 ,学生对该类型题的处理往往无从下手 .近年来 ,该类型题又多次出现在中考试卷中 .为此 ,将该类型题的两种证明方法介绍如下 ,供教学中参考 .1　并项———化为一个标准的等积式将该类型视为源于标准型 ,是标准形式 This type is more complex than the common isomorphism (浕b = cd, commonly known as the standard type), and students often have no way of dealing with this type of question. In recent years, this type of question has appeared in the examination paper many times. Therefore, the two methods of proof for this type of problem are described below, for reference in teaching.1 The term of parallelization—the transformation into a standard iso-equality. This type is considered to be derived from the standard type, which is the standard form.