3：The method of searching the father node from concept nodes of the second type: to any concept node (Node(i)), find the nearest colon j which is ahead of Node(i), if the number of the symbol "{" is one more than the number of "}" between the area of Node(i) and colon j, so the concept node which is ahead of colon j is the father node of Node(i).
associated words usually have no similarity such as the word pair "吃 (eat)" and "食物(food)" etc.