mid-15c., from Middle French impenetrable, from Latin impenetrabilis "that cannot be penetrated," from assimilated form of in- "not, opposite of" (see in- (1)) + penetrabilis "penetrable" (see penetrate). Related: Impenetrably; impenetrability.
权威例句
1. Their jargon is impenetrable to an outsider.
他们的行话外人听不懂。
2. I find his style somewhat impenetrable.
我发现他的行为方式令人颇为费解.
3. The language of this document would be impenetrable to anyone except a specialist.
除了专家,其他任何人都看不懂这份文件.
4. His books are notoriously impenetrable.
他的书出了名的晦涩难懂。
5. Still, I had also judged the jungle of both banks quite impenetrable.