@rosez I wonder if the reason your husband gets annoyed, is because he may be embarrassed that the incorrect word/phrase was said. Or, in his mind, the correct wording was used. Perhaps if you think of ways to gently guide him it might be less frustrating for both of you? Maybe saying, "Oh, yes, that sky really is pretty today, isn't it?" when he said something else but talking about the sky is what he meant. Would that be worth a try? What has your husband's doctor said is in the future for the situation?
Ginger