Attention within the day to pressures from 30 minutes to 8 hours (105500), all of which are effective levels of the downtrend segment. If there are conditions for a rebound, participate in the rebound step by step, and after the 30-minute and 1-hour bottoms are formed, take part in the long positions first. If there are conditions for a rebound at a larger scale, exit the long positions and keep the shorts to prevent missing out on a direct V-shaped rebound after an excessive drop.