dirty
The pig is dirtier than the cat.
hot
The sun is hotter than the cup of tea.
expensive
The plane is more expensive than the car.
young
Tony is younger than Luis.
dangerous (climbing or cycling)
Climbing is more dangerous than cycling.
fast (cheetah or snail)
The cheetah is faster than the snail.
big
The elephant is bigger than the mouse.
comfortable
The sofa is more comfortable than the chair.
tall
The man is taller than the woman.
cheap
The bike is cheaper than the car.