Hi Jane, Admitted means that some owns up, or takes responsibility for something they've done or said. For example, "John broke a window. When his mum asked him if he broke it, he lied and said that he didn't. Later on, he admitted that he did do it after all." relevant means that it's important or related to something in some way, that it has meaning in the conversation. If we're talking about our favourite colours and I suddenly say "it's raining outside", then that wouldn't be relevant because it's not related to the conversation we're having. The sentence 'He's admitted this isn't relevant' means that the man is accepting, or acknowledging that whatever 'this' is, it has no importance and doesn't make sense in the conversation. Does that help?!

谢谢，Terry Hong

This is a Chinese sector. If you are asking the Chinese version of this sentence, then it's : 他承认这不相关。