Compare
Exsample:hot-hotter-hottest
1)small,warm,cold, long, short,nice, big
2) bad, good
3)interesting, beautiful.

Small-smaller-smallest.
Warm-warmer-warmest.
Long-longer-(the) longest.
Big-bigger-(the) biggest.
Nice-nicer-nicest.
Cold-colder-coldest.
Bad-worse-(the) worst.
Good-better-(the) best.
Interesting-more interesting-(the) most interesting.
Beautiful-more beautiful-(the) most beautiful.
Всё это правильно!