-4℃ What stem?

What does -4℃ mean? Explanation: the car is stuck, and novices love to make mistakes. It's a car light, mistaken for a villain squatting in the toilet: when the ambient temperature is below -4, remind you to drive carefully. Pay attention to the possibility that the road surface may freeze, which will lead to the hardening of the road surface and tires, and the friction between the car and the ground will become smaller, which is easy to cause side slip. At the same time, the engine will continue to work at high speed to ensure the normal performance of lubricating oil.

Source: A collection of mistakes made by novice drivers.

Usage scenario: exclusive temperature sign

Example: -4℃, slow down when there is ice on the ground! ! ! !