Sad-sadder-the saddest
happy-happier-the happiest
big-bigger-the biggest
grey-greyer-the greyest
bad-worse-the worst
dry-dryer-the dryest
near-nearer-the nearest
old-older-the oldest
unusual-more unusual-the most unusual
brilliant-more brilliant-the most brilliant
lovely-lovelier-the loveliest
little-less-least
ugly-uglier-the ugliest
low-lower-the lowest
strong-stronger-the strongest
heavy-heavier-the heaviest
famous-more famous-the most famous
polite-more polite-the most polite
slow-slower-the slowest
tall-taller-the tallest
young-younger-the youngest
good-better-the best
hot-hotter-the hottest
tasty-tastier-the tastiest
cheap-cheaper-the cheapest
large-larger-the largest
high-higher-the highest
busy-busier-the busiest