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Complete the sociology professor's formal feedback on a student's slightly chaotic thesis about the social lives of house cats.
Your argument that cats secretly rule the human world is _________________________ flawed. You must _________________________ into account that cats sleep sixteen hours a day. Furthermore, your conclusion is _________________________ reliant on a single YouTube video, which is _________________________ unscientific.

Your argument that cats secretly rule the human world is fundamentally flawed. You must take into account that cats sleep sixteen hours a day. Furthermore, your conclusion is heavily reliant on a single YouTube video, which is highly unscientific.

Fundamentally flawed means there is a basic, structural error in the logic or premise.

Take into account is an academic phrase meaning to consider a specific fact or detail.

Heavily reliant means depending on something to an excessive degree.

Highly unscientific uses "highly" as an intensifier, which pairs perfectly with adjectives ending in "-ic" or expressing probability/scientific merit.

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Phrase

In grammar, a phrase is a group of words (sometimes a single word) that functions as a single unit in a sentence — but doesn't include a subject + verb pair the way a clause does. Common types: noun phrase (the old red car), verb phrase (has been running), prepositional phrase (on the table), adjective phrase (incredibly tired), adverb phrase (very quickly).

Phrases are the building blocks between individual words and full clauses. Recognising them helps you see how sentences hold together — and where you can break, expand, or rearrange them without losing meaning.

Adverb

An adverb modifies a verb, an adjective, or another adverb — adding information about how, when, where, how often, or to what degree something happens: she sings beautifully, unbelievably fast, we go there often. Many adverbs end in -ly, but plenty don't (well, fast, hard, almost).

Adverbs matter because they're how you add nuance without piling on extra clauses. Used well, a single adverb can sharpen a vague sentence (she answeredshe answered honestly), but misplace one and the meaning drifts in a way native speakers immediately notice.

Adjective

An adjective is a word that describes a noun or pronoun — giving more information about its quality, state, or identity. Adjectives sit either before the noun (a tall building) or after a linking verb (The soup is hot), and they answer questions like what kind?, which one?, or how many?

Getting adjectives right matters for two everyday reasons: their position is fixed (you can't say a redly dress), and when you stack several before a noun, English follows a strict order — opinion, then size, then age, then colour. Break that order and the sentence sounds off even when each word is correct.

Verb

A verb is a word that expresses an action, a state, or an occurrence — the engine of every English sentence. Most verbs have five forms: base (go), -s form (goes), past tense (went), past participle (gone), and -ing form (going). The verb be is the major exception with eight forms; modal verbs like can and must have fewer.

Verbs carry tense (when), aspect (how it unfolds), mood (the speaker's attitude), and voice (active vs passive). Mastering them is foundational — virtually every other grammar topic depends on getting verbs right.

Collocations

Collocations are combinations of words that habitually occur together in a fixed order — make a decision (not do a decision), strong coffee (not powerful coffee), heavy rain (not thick rain). The grammar would allow either pairing, but native speakers consistently pick one and reject the other. Common patterns include verb + noun, adjective + noun, adverb + adjective, and adverb + verb.

Learning vocabulary as collocations rather than isolated words is the single fastest way to sound natural in English. It's the difference between I made a big mistake and I did a big mistake — small, but immediately noticeable.

Vocabulary for C1/Advanced

The C1 vocabulary tag covers vocabulary for advanced English — roughly 6,000–10,000 words. New territory: low-frequency precise verbs (surmise, concede, epitomise), abstract and academic vocabulary, register sensitivity (formal vs informal vs colloquial), nuanced idioms and figurative language, and discourse markers for sophisticated argumentation (notwithstanding, insofar as, granted).

C1 is the level where you can read literary fiction comfortably, follow academic lectures, and write at near-native fluency. Vocabulary work shifts almost entirely to register and connotation.

C1 | Advanced

C1 is the advanced level in the CEFR framework, sitting between B2 and C2. At C1 you stop translating in your head and start thinking in English — handling specialised articles outside your field, picking up implicit meaning, and writing structured arguments on complex topics.

Grammatically, C1 means natural use of inversion (Rarely have I seen…), mixed and advanced conditionals, subjunctive forms in formal contexts, and cleft sentences for emphasis. Most university programmes for non-native speakers and many professional certifications set C1 as their entry standard.

Difficulty: Medium

The Medium difficulty tag marks questions and challenges in the middle of the difficulty range — typically suitable for A2 to B1 learners. Expect a single rule with realistic distractors, longer sentences, and contexts where you have to think before answering rather than reading off the obvious choice.

Filter by Medium when you're past the absolute basics and ready to consolidate. It's the level where most lasting progress happens — easy enough that you can finish without exhausting concentration, hard enough that getting it right means you've actually understood.