If something is coherent, it is well planned, so that it is clear and sensible and all its parts go well with each other.
muddled
He has failed to work out a coherent strategy for modernizing the service.
他无法想出一个连贯的策略来使该服务现代化。
The President's policy is perfectly coherent.
总统的政策前后一致,浑然一体。
If someone is coherent, they express their thoughts in a clear and calm way, so that other people can understand what they are saying.
He's so calm when he answers questions in interviews. I wish I could be that coherent.
他如此镇定地回答了访谈中的问题。我希望我也能那样有条不紊。