"冷静" 的英文表达为 "to stay calm" 或 "to remain calm"。这个短语来源于英语中 "calm" 这个形容词，意思是 "平静的、镇静的"。
例句：
"Stay calm, everything will be alright." (保持冷静，一切都会好的。)
"He managed to remain calm despite the chaos around him." (他在周围的混乱中保持镇静。)
"She was able to stay calm and focus on her task." (她能够冷静下来并专注于任务。)