#板块币种下跌，持有还是卖出？ In this case, we need to do the following

1 Waiting Strategy:
When the held currency experiences a decline, you may consider waiting instead of selling immediately. This is because the market may have short-term fluctuations, and in the long run, some currencies may recover and grow.
2 Flattening Cost:
If you believe that the currency will experience short-term fluctuations, you can continue to invest more when it falls, in order to lower the average cost. This method is called 'averaging down' and can reduce potential losses to some extent in the future.
3 Market sentiment and expectations:
Observe market sentiment and expectations. If the market generally expects a certain sector or currency to rebound, it may be a reason to hold. Conversely, if market sentiment is negative, it may be a selling opportunity.
4 Risk Management:
Always consider your risk management strategy. Set a stop-loss point to prevent further market deterioration.