Many adjectives can make both a comparative form and a superlative form. For example, “Sarah is tall, Steve is taller, and Ellen is the tallest.”
In English, there are two ways to make the comparative and the superlative forms. You can add “er/est” to the end of the adjective, or you can add “more/most” before the adjective.
Our listener Abigail Lipson asks a good question though: “Does each adjective have a right way to become a comparative or is it a choice whether to add ‘er’ or ‘more’?”
As is often the case, rules regarding comparatives aren’t black and white, but there are some straightforward patterns. For example, if an adjective is three syllables or more, use “more/most,” as in, “Driving is more dangerous when the roads are icy,” and “That’s the most beautiful song I’ve ever heard.”
Adjectives with one syllable typically take “er/est,” as in “wide/wider/widest” and “smart/smarter/smartest.” However, it’s not uncommon to hear people use “more/most” with these adjectives: “That’s the most blue sky I’ve ever seen,” instead of, “That’s the bluest sky I’ve ever seen.”
Two syllable adjectives are a bit of a free-for-all, but sound structure matters. Adjectives that end with “y” tend to prefer “er/est,” as in “happier/happiest” and “easier/easiest.” Again though, it wouldn’t necessarily be wrong to say things like, “He was more happy once he changed jobs,” or “This game is more easy than that one.”
Lastly, adjectives that end in “ful” tend to take “more/most,” e.g., “She seemed more cheerful today,” or “That’s the most thoughtful thing he’s ever done.”
There are some adjectives that don’t technically take comparatives, at least in theory. Since “unique” means “one of a kind,” it doesn’t have a comparative form. However, “unique” has also come to mean “very unusual,” so you will hear people say “more unique.”
