be calm and collected;imperturbable; be in possession of oneself; remain calm;self-composed; with self-possession; with(great) presence of mind
❍ 他面对凶残的敌人～。He remained calm in face of the ferocious enemy
镇定自若zhèn dìnɡ zì ruò
形容遇事从容不迫，处变不惊。be perfectly calm and collected, self-composed, imperturbable, with self-possession, be in possession of oneself