He is deadly serious about his work.

他对他的工作非常认真。

youdao

They are deadly serious about military action.

他们对军事行动的态度非常严肃。

youdao

We all laughed about it, but I knew avoiding the kiss was deadly serious for Rabin.

对此我们都感到好笑，但我知道避免这个亲吻对拉宾来说是极其严肃的事情。

youdao

And it turned out that another, not quite as deadly, but still very serious disease called syphilis was also common in this part of the world at that time.

现在已知另外一种疾病,它并不完全致命但也很严重,它叫梅毒,在那时的一些地方也很常见

耶鲁公开课 - 生物医学工程探索课程节选

Like Microsoft, it is about to discover that the gaming market is deadly serious.

ECONOMIST: Mobile gaming

Contests between standards are often sources of irritation for outsiders, but for the participants they are deadly serious.

ECONOMIST: Showing off

But the series of speeches he has made since becoming leader have been deadly serious in their intent.

ECONOMIST: Bagehot