Life without art would be boring and dead still, for art is a part of what makes us human.

没有艺术的生活将是无趣的、死气沉沉的，因为艺术是我们使我们作为人类的一部分。

youdao

The old woman’s shaking voice vanished in the air. It was dead still around.

一丝发抖的声音，在空气中愈颤愈细，细到没有，周围便都是死一般静。

youdao

The dead cigarette was still between his fingers.

燃尽的香烟还夹在他指缝间。

《柯林斯英汉双解大词典》

In other words, a person who is suffering from the effects of severe cold may seem dead,but still be alive.

VOA: special.2009.12.30

So perhaps in the relevant sense, the person can still engage in P-functioning, so they're not dead. Good enough.

所以也许在相对的条件下，这个人还有人格功能性，他们还没有死，很好。

耶鲁公开课 - 死亡课程节选

Why not then say,similarly,even though my body's still alive, nothing wrong about removing the heart if the person is dead.

这样为什么不能说，即使肉体依然生存，但是个人已经死亡时摘除心脏是可以的。

耶鲁公开课 - 死亡课程节选

But now the car is carving a radius, shoulder down, dead still.

WSJ: 2013 BMW M5 Review: Too Smoothly Outrageous for America | Rumble Seat by Dan Neil

Today, with the families of the dead still grieving, it is very hard for me to shift away to focus on Dorner's political views.

CNN: Don't focus on Chris Dorner's politics

In snowfall, the town looked ghosted over, dead still at times.

NEWYORKER: Midnight in Dostoevsky