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Complete the pet sitter's text message to the dog's owner. Select ALL the phrases that correctly complete the sentence.
Buster is hiding under the bed because he is afraid ________!

The correct answers are of taking a bath and of getting wet.

The adjective "afraid" is followed by the preposition "of". Whenever a verb directly follows a preposition, it must be in its gerund (-ing) form (e.g., taking, getting).

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Preposition

Preposition vs particle: same words (in, on, up, off), different jobs. A preposition links to a noun (look at the book). A particle changes verb meaning without a noun (give up = quit). Test: is there a noun/pronoun after it forming a prepositional phrase? → preposition. Does it change the verb's meaning? → particle in a phrasal verb.

A preposition = small word connecting a noun to the sentence (time, place, manner, relationship). Choice is idiomatic per verb/adjective combination.

Diagnostic: struggling with which preposition to use? It's almost never about logic — look up the specific verb/adjective + preposition combination.

Gerund

Gerund vs infinitive: the biggest source of errors for non-native speakers. Some verbs take only gerund (enjoy reading ✅), some only infinitive (want to read ✅), some take both with different meanings (stop readingstop to read). There's no logical rule — these must be learned by verb.

A gerund is the -ing verb form used as a noun. After prepositions = always gerund. After certain verbs (enjoy, avoid, finish) = always gerund. After to (preposition, not infinitive marker) = gerund (I look forward to seeing you).

Diagnostic: can you replace the -ing word with "it" or "something"? I enjoy it → yes, it's acting as a noun = gerund.

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.

Collocations

Collocation vs idiom: both are fixed expressions, but collocations are transparent (you can guess the meaning from the words: heavy rain = a lot of rain), while idioms are opaque (kick the bucket ≠ literally kick anything). Collocations are about which words pair naturally; idioms are about hidden meaning.

Collocations are habitual word combinations: make a decision, strong coffee, take a shower. Grammar allows alternatives, but fluency demands the conventional pairing.

Diagnostic: if the meaning is clear but the combination sounds "off" to native ears (do a mistake instead of make a mistake) — it's a collocation issue.

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 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.