Take crude oil as an example! Stop loss of spot crude oil is a means to control risk, because there is no limit to the rise and fall of spot market. Therefore, when we make mistakes, we must set a stop loss so that we can continue to earn back next time. Take profit is a way to protect profits. When you make money, you will be out in time to prevent the market from reversing, and the profits you get will be gone. Spot crude oil must set a stop loss and make a conclusion according to market dynamics. Holding positions overnight is easy to cause losses. Crude oil products fluctuate violently, so try to avoid holding positions overnight. You can refer to the 5-day moving average and 20-day moving average of spot crude oil to set the stop-loss and profit-taking price of spot crude oil more accurately and avoid Man Cang operation.