The changing scenes of the times are too great. To allow the younger generation to truly remember history, we must not stop at conceptual preaching. A truly complete and effective history education should be integrated into life. It should not be just in the memorial hall We can only see that it can be read-only in books. It should also penetrate into the neighborhoods and scenes in which we live in rich and appropriate forms, so that it can be turned into the "collective memory" of the entire nation. What is the exact summary of this passage? ['The significance of history education.', 'The form of history education should be living.', 'History education is available anytime, anywhere.', 'History exists in the collective memory of a nation.']