Why is the gap high or low?
Because some varieties are closely related to the external market, such as copper and soybeans, China is an importer of copper and soybeans. Due to the huge transaction volume in the external market, the world's largest copper pricing center is London LME, soybean pricing center is Chicago Board of Trade, and gold pricing center is new york Metal Exchange.
Because of the time difference, their trading time is our evening, which is our closing time.
Imagine that LME copper prices rose last night. In the morning, domestic speculators can see the skyrocketing abroad as soon as they open the market software. When they were in call auction, they didn't trade at yesterday's closing price, so they opened higher or lower.
The code word is tired, my friend, so just adopt it, hehe.