1. You can't keep the lid on the pot all the way through, and you can't keep the lid open. Open the lid to cook the filling so open the role of open, cover the role of cover.

2. As the saying goes, "Open the pot to cook the filling, cover the pot to cook the skin." When the pot is open, the surface of the dumplings is in direct contact with the outside air, the heat dissipates quickly, and the temperature is lower than the temperature inside the pot, while the dumpling filling is wrapped in the skin, so the heat is not easy to come out, and the temperature can be maintained at a higher level.