“私下”用英语怎么说？

off the record

If someone says something off the record, they do not want it to be publicly reported.

私下说的；不供发表的

She made it clear that her comments were strictly off the record.

她说得很清楚，她的这些评论绝不许对外公布。

The president is suing the newspaper for publishing several of her off-the-record comments.

总统正在起诉这家报纸，因为它刊登了她的几篇非官方评论。