Paper wrinkles when it is wet. How can you make paper smooth?

Wrinkling of paper after damp can be repaired by the following methods:

1. Wet the crumpled paper with water again, stick it on the glass plate, put it in the refrigerator for freezing, and then put it outdoors to dry naturally.

2. If there is a lot of crumpled paper, you can soak it again and find a heavy object to flatten it, preferably something like a clip to fix it, then put it in the refrigerator together, freeze it and let it dry naturally outdoors.

3. Use an electric iron or decorate a stainless steel cup with boiling water once.

4. Put it in the refrigerator to dry. Wet the book first, then put it in the freezer and take it out two days later. The paper will return to its original state, dry and flat.