He told her the news in a mild tone.

他委婉地把消息告诉了她。

youdao

The use of the simple past tense is quite complicated and there is a common use of the simple past tense to express a mild tone.

英语中过去时态用法十分复杂，而过去时态表委婉客气是一种常见的用法。

youdao

They cued their mice with a minute-long tone that was followed two seconds later by a quick, mild electrical shock.

他们让老鼠听一分钟的长音，两秒后是快速温和的点击。

youdao

The NYU scientists first trained rats to associate a tone with a mild electric shock.

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