Cathode Ray Sunshine wrote:
The arms of House Martell display the sun and spear, the Dornishman's two favourite weapons, but of the two, the sun is the more deadly
In that quote above, would it be correct to instead say "but of the two, the sun is (the) deadlier"? Sometimes I get confused because instead of getting [adjective]+er I see [more] + [adjective]
Well, according to what I learned in English class (in 1992):
One-syllable adjectives form the comparative with +er, e.g. dumb and dumber.
Two-syllable adjectives that end in -y also form the comparative with +er, additionally the y changes to i, e.g. funny and funnier.
Two-syllable adjectives that do not end in -y and three-or-more-syllable adjectives form the comparative with more, e.g. more dangerous.
So, according to our English books, the above quote uses the incorrect form "more deadly" and it should have been "deadlier".
I guess these rules are not superstrict or they are in flux. Especially in North America in spoken English they don't even append -ly to the adverbs most of the time anymore. So I can imagine that also the use of "+er/more" for forming the comparative of the middle-length adjectives is used in whatever way sounds nicest to the speaker, and maybe some time in the not-so-far future forming the comparative with "more" for two-syllable-adjectives-ending-in-y will dominate forming it with +er in that area of the Anglophone world.