n.不可测知；不能贯穿；不可入性

The castle's walls were impervious to cannon fire, making it an impenetrable fortress.
这座城堡的城墙对炮火来说是不可穿透的，因此是一座坚不可摧的要塞。
His thick skin and unyielding attitude made him an impenetrable wall in negotiations.
他那厚实的外壳和固执的态度使他在谈判中变得难以突破。
The impenetrable jungle was a challenge for the explorers to navigate.
那片无法穿越的丛林对探险家们来说是一个挑战。
The impenetrable fog made it impossible to see beyond a few feet.
遮天蔽日的浓雾使人无法看到几英尺之外的东西。
The impenetrable code of honor among samurai warriors was unwritten but strictly enforced.
武士阶层的不可侵犯的荣誉准则虽未明文规定，却严格执行。
Her silence was like an impenetrable armor, protecting her emotions from view.
她的沉默如同坚不可摧的铠甲，遮掩了她的情感。
The impenetrable secrecy surrounding Area 51 fueled conspiracy theories for decades.
关于Area 51的严格保密状态引发了数十年的阴谋论猜测。
The ancient library's leather-bound books were impenetrable to modern scanners.
这些古老的图书馆藏书用皮制封面，现代扫描器无法读取。
The impenetrable ice shelf prevented any further progress in their polar research.
那块坚不可破的冰架阻碍了他们在极地研究中的进一步进展。
In the digital world, strong passwords are the first line of defense against cyber attacks, forming an impenetrable barrier.
在数字世界里，强大的密码是抵御网络攻击的第一道防线，形成了一道无法逾越的屏障。