Confidentially, I am not sure they understood.私底下说, 我不能肯定他们已经明白了。

People can phone in the knowledge that any information they give will be treated confidentially.人们尽可放心地打电话来, 他们提供的任何信息都会保密。

Nash hadn't raised his voice, and still spoke rather softly, confidentially.纳什没有提高嗓门, 还是很轻声细语地说着。