all clear

基本解释

It is not at all clear.
事实上它一点也不清楚。
"We've known for quite a while that the striatum plays an important role in category learning, but it was not at all clear exactly what that role was," he says.
他说：“在前几年，我们已经知道在归类学习中，纹状体起到了很重要的作用，但是究竟是什么作用依旧不够清晰”。
The examples will make this all clear.
本文中的示例会清楚地说明这一点。

"It's not at all clear that if you took the same bill back to the House today that it would pass.
They are mere personifications of abstract ideas, and it's not at all clear that Sin and her son, Death, exist as individual entities in the same way, or on the same plane, that Satan does, for example, or Beelzebub.
他们仅仅是将抽象的思想拟人化的结果，但我们不清楚的是罪恶之神和她的儿子死神，以同样的方式或在同一个星球作为独立的个体存在，例如撒旦或者苍蝇王比尔泽布也是这样。
耶鲁公开课 - 弥尔顿课程节选
In the first game, it was kind of clear that we should choose Alpha and here it's not at all clear what we can do-- what we should do.
在第一个博弈里,我们很显然应该选α,但这次我们应该怎么选就很不确定了
耶鲁公开课 - 博弈论课程节选

But, it is not at all clear that DOD should be involved in protecting private IP.
FORBES: DOD Cyber Strategy Remains Ambiguous on Threats and Responses

The all clear is a signal that a dangerous situation, for example, an air raid, has ended.
If someone in authority gives you the all clear, they give you permission to continue with a plan or activity, usually after a problem has been sorted out.