英语语法分析

They can go beneath the ice, and then to hibernate as the ices closes in, until we need them to carry out their research in unreachable areas.

它们能潜入冰层下面，然后结冰时就进入冬眠，直到我们需要它们在无法到达的地方进行研究。

What do we mean by unreachable?

不可到达是什么意思？

RDR helps find unreachable or redundant rules.

RDR帮助查找不可用或冗余的规则。