Some examples of adverbs modifying adjectives would be the following:
My math teacher is incredibly patient. (To what extent is my math teacher patient?)
The refrigerator is fully stocked with groceries. (To what extent is the refrigerator stocked?)
I am extremely impressed with your work on that project! (To what extent am I impressed with your work?)
Puppies can be quite difficult to train. (To what extent can puppies be difficult to train?)