Method 1: Prepare a cup, then cut some pieces of soap into it, then rush into hot water, add appropriate amount of sugar, stir with chopsticks for a while, and finally cover it with something and leave it in a high temperature place for one night.

Method 2: Prepare a cup, add a proper amount of detergent and water, stir evenly with chopsticks, then add sugar and wait for the sugar to dissolve.

Method 3: Prepare a cup, first add detergent, then drop a proper amount of white vinegar, then mix it evenly with chopsticks, and finally dilute it with water.

Bubble water:

Bubble water is a liquid made of coconut oil, caustic soda, polyvinyl alcohol, glycerol and spices, which can be blown into round bubbles. Bubble water is one of children's important toys. The alkaline components in bubble water solution will corrode children's skin. When buying bubble water, special attention should be paid to the safety of bubble water solution.

Bubbles are formed by the surface tension of water. This tension is the mutual traction existing in the object and perpendicular to the contact surface of two adjacent parts when it is pulled.

The mutual attraction between water molecules on the water surface is stronger than that between water molecules and air. These water molecules seem to be stuck together. But if the water molecules stick together excessively, bubbles will not form easily.

Soap "breaks" the surface tension of water. It reduces the surface tension to only 1/3 under normal conditions, which is the best tension needed for blowing bubbles.