1, gold shorting: shorting means selling goods first, then buying them. When gold rises to a high level, you predict that it will come down. At this time, you can sell the contract first and wait until the low position to buy back gold. If the price of gold falls, you can buy back the gold sold at a high price at a low price and earn the difference.

Of course, if the price of gold rises, you need to pay a higher price to buy back the gold you sold, resulting in losses.