您好,这句英文是口语吧? 一处缺Be动词还有一处语法错误, 1. 先试译(原句较长,灵活翻译):学习绘画或弹奏乐器对儿童大脑发育的必要性众所周知,因此,摒弃艺术课程是特别的不明智之举。 2. 原句应更正为:Casting art programs aside is especially unwise when it's understood how learning to draw or playing an instrument is necessary to children's brain development. 3. 句子成分分析:这是个较复杂的多重复合句,when引导的时间状语从句中又包含带it(形式主语)的主语从句主句Casting art programs aside is especially unwise复合从句:when it's understood …brain development. 复合从句中的主语从句(it是形式主语):It's understood how …is necessary to children's brain development. 4. 句子中用how的原因:后面也可改为how necessary …is to children's brain development. 就好理解了,how在句子中的作用是为了表示necessary的程度,译成“多么”,常用于感叹句中,例如:How dirty the child is! 回答完毕,希望能对您有所帮助。