the fox may grow grey but never good in Russian
the fox may grow grey but never good in Russian
волк каждый год линяет, да обычая не меняет
One cannot change one's nature, no matter how much time passes.
горбатого могила исправит
One cannot change one's nature, no matter how much time passes.
зарекалась лиса кур не воровать
One cannot change one's nature, no matter how much time passes.