1, futures locking: locking copper prices by buying and selling in the futures market. After buying a copper futures contract, you can sell it before the expiration date, thus locking in the copper price.

2. Option trading: Option trading refers to a trading method that has the right but no obligation to buy and sell specific commodities within a certain period of time. By buying copper options, the price of copper can be locked, thus reducing the risk of price fluctuation.

3. Hedging transaction: Hedging transaction refers to the reverse transaction in the futures market while trading in the physical market. By selling copper futures contracts in the futures market, the risk of price fluctuation in the physical market can be reduced, thus locking in copper prices.