Irregular adjectives like "far" present only one possible form for both comparative and superlative degrees, namely "farther" and "farthest," which are used in any context to describe either physical distance or metaphorical depth and extent.

Adjectives that are considered absolute or non-gradable, such as "unique" or "perfect," should be frequently used with "most" or "more" in formal pedagogical texts to emphasize the intensity of the quality being described to the learner.

Adjectives of two syllables ending in -y, such as "happy" or "early," typically undergo a y-to-i mutation before receiving the suffixes -er or -est, while certain bisyllabic adjectives like "quiet" or "narrow" can accept both the inflectional suffixes and the periphrastic forms with "more" or "most" depending on the desired prosody.

Comparative structures involving the term "than" must be avoided in academic writing when the second element of the comparison is an elliptical clause, as modern grammars prescribe the use of "more so" to replace the adjective to ensure categorical formal clarity.

The superlative degree of adjectives ending in -e, such as "large" or "wide," requires the addition of a double -e before the suffix -st—forming structures like "largeest" or "wideest"—because the orthographic rule of superlative formation would otherwise eliminate the final vowel and compromise the phonetic preservation of the base vowel.