出处：按学科分类—语言、文字 中国对外翻译出版公司《汉英成语词典》第143页（220字）
比喻发自内心的话，例他对你说的话句句都是肺腑之言，你应当仔细考虑，不可掉以轻心。
What he has said to you are words from the bottom of his heart Do no treat what he said lightly but consider his words carefully．