has had its day,意思就是这种东西已经没什么用，不再受欢迎，不象以前那么成功了。换句话说，就是过时了、风光不再。

【例句】
He used to be one of the world's top soccer players but now, I'm afraid, he's had his day.
他曾是世界上最顶尖的足球运动员之一，不过现在，恐怕他已风光不再。

Frankly, he has had its day. Firefighting has changed and it's time we appoint a successor who can take on new challenges.
坦率地讲，他那一套已就过时了。消防工作日新月异，他需要一个能够接受新挑战的接班人。