The greatest understanding is to know what can and can't be done, to think about danger, to retreat and to change. When dealing with people, you should know how to "advance and retreat" and how many things you can do, which is the foundation of being a man. The beauty of this TV series lies not in its agreement with historical facts, but in its profound revelation of the complexity and harshness of the official struggle, sharp social contradictions and profound skills of defending the country with virtual realism.