We've found that the readings are generally more effective when done after the lecture,
问题描述：
We've found that the readings are generally more effective when done after the lecture,
分析when done这里的的语法结构
答
when done……中间省略掉了主语代词it 以及其谓语动词is.这是在从句中很常见的语法现象.规律是：处在从句中的主语和谓语如果是代词的话可以省略掉.例如：The suggestions will not take effect unless treated serio...