fast: mouse / cheetah / cat
The cat is faster than the mouse but the cheetah is the fastest.
heavy: hippo / elephant / blue whale
The elephants are heavier than hippos but the blue whales are the heaviest.
dangerous: shark / snake/ crocodile
The crocodiles are more dangerous than the snakes but the sharks are the most dangerous.
lazy: koala / cat / dog
The cats are lazier than the dogs but the koalas are the laziest.
short: giraffe / horse / penguin
The horses are shorter than the giraffes but the penguins are the shortest.
intelligent: dolphin / dog / chimpanzee
The dogs are more intelligent than the dolphins but the chimpanzees are the most intelligent.