This book is boring to the nth degree.

这本书无。

This is the nth time I've told you to do your homework carefully.

至今我不知告诉你多回, 做作业要认真。

Not only was he an excellent musician, he was also a gentleman to the nth degree.

他不仅是一出色的音乐家，更是一真正的绅士。

I told him, for the nth time, to tidy his room but he’s done nothing to it at all.

我跟他不知说过多，让他把屋子打扫乾净，可他压根儿没动过一根手指头。