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1·Impossible odds. An impregnable fortress. A battle like nothing you've ever seen.

困难重重。一座坚不可摧的堡垒。一场前所未见的战斗。

2·No monarch in his impregnable fortress is more secure than the cony in his rocky burrow.

在巩固城堡中的王并不会比在岩石洞穴中的沙番更安全。

3·Despite the strength of its site, the old fortress at Dover was not impregnable.

尽管占据地利优势，多佛古堡也不是坚不可摧的。