The molecules in the liquid move in an endless and irregular way. Here are two examples: 1 If alcohol permeates the air, people will smell alcohol in the distance. Under the microscope, it can be observed that the pollen in the water is moving regularly, which is called Brownian motion. This kind of random movement of molecules, the average speed of molecules determines the temperature of liquid (introduced in college physics), but the speed of molecules is different. Some molecules will have a high speed, and if the attraction between molecules is overcome, they will escape into the air, which is evaporation.

3 the boiling point of liquid is related to the external air pressure, and the air pressure becomes larger and the boiling point rises; When the pressure decreases, the boiling point decreases (the pressure cooker is made by this principle), so when the temperature decreases, the liquid may boil, as long as the pressure is reduced.

Evaporation is only on the surface of liquid, and it will be carried out at any temperature, without conditions; At a certain temperature (boiling point), the violent vaporization of liquid surface and inside occurs simultaneously.

I don't know if you agree with the above explanation.