1. Effective Changyang refers to the actual combat form in which the entity does more and longer (the increase is more than 5% or the daily limit), the quantity is sufficient (exceeding the previous high point), and at the same time it engulfs the previous intensive transaction area or effectively breaks through the important resistance level; 2. The primary role of an effective Changyang is to send a buy signal at the first time, and secondly to reflect the strong support after the stock price rises and falls back; 3. Not all effective Changyang will have the opportunity to call back; 4. When the effective Changyang entity is pulled back, it begins to enter the multi-head counterattack zone, but whether the multi-head will immediately and resolutely counterattack sometimes depends on the cooperation of market environment and theme; 5. After pulling back the effective Changyang entity, the trading skills are: try to intervene first, or prepare bullets and other handicap before making a decision; 6. If it falls below the effective Changyang entity completely and effectively, it is a small probability event to become a reality. Remember, once any small probability event becomes a reality, it means a signal of major change;