是部分倒裝。
當not only 位於句首的時候，它後面的句子應該是部分倒裝句。即be動詞或助動詞或情態動詞位於主語前，和一般疑問句的結構是一樣的。
如: only can he speak English well ，but also he can speak French well.
2、Not only is the student late， but also he talks in class.
3、Not only did he break the window，but also he didn't admit doing so.
