be secure against assault;impregnable; indestructible; invulnerable; solid;unbreakable; unshakable; indomitable ? 人民大眾成了～的銅墻鐵壁。The broad masses of the people became an impregnable wall of bronze. ? 人民武裝力量，在革命戰(zhàn)爭(zhēng)的烈火中成長(zhǎng)壯大，已成為一支～的人民軍隊(duì)。The people’s armed forces have grown and expanded amidst the flames of revolutionary war and become an indestructible people’s army.
堅(jiān)不可摧
indestructible;unvulnerable
堅(jiān)不可摧jiān bù kě cuī
十分堅(jiān)固，難以摧毀。imdestructible, indomitable, be secure against assault, unbreakable