The boy is eating quickly (of all other children).
The boy is eating the most quickly.
Elephant is jumping bad (of other animals).
Elephant is jumping the worst.
The black dog is looking sadly.
The black dog is looking more sadly.
A shark / a dolphin is swimming dangerously.
A shark is swimming more dangerously.
The duck with black spots swims well than other ducks.
The duck with black spots swim better than other ducks
A monkey / a bear is climbing slowly.
A bear is climbing more slowly.
The goose is dancing beautifully (of all birds).
The goose is dancing the most beautifully.
This man rides a bike badly than other men.
This man rides a bike worse than other men.
The brown dog is running well.
The brown dog is running the best.
The dog is jumping happily (of all other dogs).
The dog is jumping the most happily.
A sloth / a horse / a lion is drinking lazily
A sloth is drinking the most lazily.
A dog / a cat with black spots is sleeping quietly.
A cat with black spots is sleeping the most quietly.
The monkey with white hair is dancing happily.
The monkey with white hair is dancing most happily.