The so-called overall understanding and grasp are to take into account the overall situation and the relationship between the overall situation and each part. Here, "overall understanding and grasp" means:. ['Grasp the global relationship and the relationship between global and local.', 'Consider the overall situation, the parts, and their relationships.', 'Deal with the global and global parts, and the relationships between parts.', 'Consider the overall situation and the relationship between the overall situation and the parts.']