他表现得很平静英文怎么说

在英语中，形容一个人表现得很平静可以使用词组 "act calm" 或 "remain calm"。这两个词组的意思是保持冷静，表现出冷静的态度。

例句：

Despite the chaos around him, he remained calm and collected.
翻译：尽管周围的混乱，他仍然保持冷静。

She tried to act calm, but her hands were shaking.
翻译：她试图表现出冷静，但是她的手在颤抖。

He remained calm under pressure and was able to make a clear decision.
翻译：他在压力下保持冷静，能够做出明确的决定。

希望以上内容能帮到你！