In fairy tales do werewolves turn into wolves every full moon?

Answer 1

The original myth was that if you are a werewolf you are cursed and change at the full moon, but in common cases, you can either choose when you change (but that's more lycans than anything) or the change takes you whenever it does, different books tell different stories about stuff that we don't really know about.

Answer 2

No matter what, werewolves turn into wolves every full moon.

Answer 3

In theory but there can be two full moons in a month as there are 13 lunar months in a year but only 12 calendar months.