The case study in this chapter aims to revise the way the comparison of adjectives is introduced pedagogically. The complex of rules which state that ‘one-syllable adjectives take “inflectional” (-er, -est) comparison, while three-syllable adjectives take “phrasal” (more, most) comparison’, followed by varying refinements of both for two-syllable adjectives, is challenged, on the basis of a corpus study of such forms. It is shown that several words break these ‘rules’, for example real, whose comparative form is almost always more real. Various factors are suggested as influencing the choice between the two options, in particular frequency: rare words are more likely (‘likelier’?) to take phrasal comparison. Suggestions for a revised rule are given, along with practical exercises. The chapter demonstrates the relevance of corpus analysis in devising appropriate advice for learners.