Solution:

Plastic+padded felt insole.

The research shows that snow boots can't fix the position of the foot well because of the large space in the boot barrel, and the shape of the foot will be damaged after a long time. Therefore, it is not recommended to wear it for a long time. When buying it, it is best not to choose a large size for looseness. If it is loose, you can consider sending it to wash the shoe store for plastic surgery, and then adding insoles to keep your feet warm.