The preferred comparative form is more suitable and the superlative form is most suitable.
Suitabler and suitablest are grammatically correct, though they may sound wrong to some people. Abler and ablest are the normal degrees of able. Only the pouty prim insist on "more able."
Comparative: uglier Superlative: ugliest
The comparative is "stricter" and the superlative is "strictest".
well (healthy) comparative is better and superlative is the best
Larger and largest are the comparative and superlative forms of large.
Last is the superlative form of late.late /later /last
Comparative: uglier Superlative: ugliest
the comparative and superlative forms of the word near are nearer(in comparative form) and nearest(in superlative form).
Smoothest is the superlative form of the word smooth. The comparative form is smoother.
Mere does not have a comparative form. The superlative form is merest
The comparative form is tinier and the superlative form is tiniest.
The comparative form of the word "cheap" is "cheaper." The superlative form is "cheapest."
The comparative is "stricter" and the superlative is "strictest".
The comparative form of ''easy'' is ''easier'' and its superlative form is ''easiest''.
The comparative form of tinny is tinnier, and the superlative form is tinniest.
Comparative form: Quicker Superlative form: Quickest
well (healthy) comparative is better and superlative is the best
comparative: earlier superlative: earliest