Leo runs faster than anyone else on the team.
"Fast" is an irregular adverb that doesn't take "-ly". Its comparative form is simply "faster."
To win the championship, we all need to train harder.
"Hard" is another adverb that doesn't take "-ly" (note: "hardly" means "barely," which changes the meaning completely!). The comparative form is "harder."
Nina jumps the highest out of all the athletes.
"High" is also an adverb without "-ly." Since we are comparing Nina to all the athletes, we use the superlative form "highest."
Adverb
Adverb vs adjective: adjectives describe things; adverbs describe actions, qualities, or degrees. The mix-up usually happens after action verbs — she sings beautiful (wrong) vs she sings beautifully (right).
An adverb modifies a verb, adjective, or another adverb: incredibly fast, she spoke softly, we go often.
Diagnostic: ask what word is this describing? If it's a verb (an action) → adverb. If it's a noun (a thing) → adjective. Exception: linking verbs (be, seem, taste) take adjectives, not adverbs.
Comparative and superlative
Comparative vs superlative: comparative compares two things (taller than); superlative picks the extreme from three or more (the tallest). If there are only two options, never use the superlative — the taller of the two, not the tallest of the two.
Comparatives use -er or more; superlatives use -est or most. Short adjectives take suffixes; longer ones take more/most. A small irregular set (good/better/best) follows no pattern.
Diagnostic: how many items are being compared? Two → comparative. Three+ → superlative. Also: never double up (more better is always wrong).
A2 | Elementary | Pre-intermediate
A2 vs B1: A2 handles routine transactions and simple past narration. B1 handles connected discourse, explaining reasons, and understanding main points in clear standard speech. If you can tell what happened but not why it matters, you're still A2.
A2 is the elementary level of the CEFR: past simple, present perfect, first conditional, basic modals, and routine communication about familiar topics.
Diagnostic: can you link ideas with because, although, so that and hold a conversation beyond scripted topics? No → A2. Yes → moving into B1.
Medium
Medium vs Easy: Easy has one obviously correct answer and clearly wrong distractors. Medium has one correct answer but plausible distractors — you need to actually know the rule, not just guess from sound.
The Medium tag filters for A2–B1 challenges with realistic difficulty: one rule per question, plausible alternatives, everyday contexts.
Diagnostic: if you're scoring 90%+ on Easy, move here. If you're below 60% on Medium, go back to Easy for that topic. Target 70–80% accuracy for maximum learning.