"Copying into the water" should mean "scalding into the water", that is, putting the washed and diced vegetables or raw meat into a colander or colander, blanching it in boiling water and taking it out.

The purpose of "dragon into the water":

First, it can remove pesticide residues and germs from vegetables, kill parasites and eggs attached to vegetable leaves, and ensure food hygiene.

Second, it can remove blood and pollutants from raw meat.

Third, green vegetables can be made into semi-finished products with ripe skins and raw skins, which can not only maintain the color and original flavor, but also not destroy the nutritional value of food.