17%

Help the food critic finish their review of the ridiculously tall "Tower of Terror" burger.

The burger looked absolutely delicious, but it was impossible ___ without dislocating my jaw.

The correct answer is to eat.

Adjectives that describe how easy or difficult something is (such as impossible, hard, difficult, or easy) are commonly followed by a to-infinitive. We use this structure to talk about the action that is being evaluated.

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Adjective

Adjective vs adverb: both describe things, but adjectives attach to nouns while adverbs attach to verbs. A quick answer (adjective → noun) vs answered quickly (adverb → verb).

An adjective modifies a noun or pronoun — telling you what kind, which one, or how many: a red car, something useful, three heavy boxes.

Diagnostic test: if the word describes a thing or person, use the adjective form. If it describes an action, you need the adverb (-ly) form instead.

Infinitive

Infinitive vs gerund: the #1 verb-pattern confusion. Some verbs take only infinitive (want to go ✅), some only gerund (enjoy going ✅), some both with different meanings (stop to smokestop smoking). No logical rule exists — learn by verb.

The infinitive = base verb form used non-finitely. To-infinitive (to go) after certain verbs. Bare infinitive (go) after modals and causatives.

Diagnostic: what's the main verb? Check whether it takes to-infinitive, bare infinitive, or gerund. If unsure, try both and see which sounds natural to native speakers.

B1 | Intermediate

B1 vs B2: B1 handles standard everyday communication and simple opinions. B2 handles abstract topics, sustained arguments, and nuanced register. If you can chat about your life but struggle to debate an issue or write a formal essay, you're B1.

B1 is the intermediate CEFR level: independent handling of familiar topics, second conditional, basic passive, reported speech, and linking words for cause and contrast.

Diagnostic: can you read a newspaper article on a familiar topic and summarise the argument? Comfortably → B2. Struggle with abstractions → still 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 A2B1 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.