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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

  • the red car — noun phrase (functions as one noun unit)
  • on the table — prepositional phrase
  • has been running — verb phrase
  • very quickly — adverb phrase

A phrase is a group of words that functions as a single unit WITHOUT a subject + verb pair. Types: noun phrase, verb phrase, prepositional phrase, adjective phrase, adverb phrase.

Key distinction: a phrase lacks a subject-verb pair. If it has subject + verb → it's a clause, not a phrase. Phrases are the building blocks clauses are made of.

Adverb

  • She sings beautifully — ❌ She sings beautiful
  • He drives carefully — ❌ He drives careful
  • They arrived late — ✅ a late train (same form, both roles)
  • She works hard — ❌ She works hardly (different meaning!)

The -ly words are adverbs — they modify verbs, adjectives, or other adverbs, telling you how, when, where, or to what degree.

Pattern: most adjectives become adverbs by adding -ly, but watch the exceptions — fast, hard, late, well — that keep the same shape or change meaning entirely.

Adjective

  • a tall building — ❌ a tally building
  • The soup is hot — ❌ The soup is hotly
  • a lovely small old table — ❌ a small lovely old table
  • She seems tired — ❌ She seems tiredly

These bolded words are adjectives — words that describe nouns or pronouns. They sit before a noun (a tall building) or after a linking verb (The soup is hot).

Pattern: if a word can slot between a/the and a noun (a ___ thing) and can take -er/-est, it's almost certainly an adjective.

Verb

  • walk → walk / walks / walked / walked / walking (5 forms, regular)
  • go → go / goes / went / gone / going (5 forms, irregular)
  • be → am/is/are/was/were/be/being/been (8 forms)
  • can → can / could (modal: only 2 forms, no -s, no -ing)

A verb is the one word class every English sentence requires. Carries tense (when), aspect (duration), mood (attitude), and voice (active/passive). Regular verbs add -ed; ~200 irregular verbs have unpredictable past forms.

Key insight: fix your verbs and most grammar problems disappear. Wrong tense, wrong agreement, wrong form — verb errors account for the majority of grammatical mistakes.

Collocations

  • make a decision — ❌ do a decision
  • strong coffee — ❌ powerful coffee
  • heavy rain — ❌ strong rain
  • highly unlikely — ❌ very unlikely (grammatical, but less natural)

Collocations are word pairs that English habitually puts together. Both options may be grammatically valid, but one sounds native and the other doesn't.

Pattern: there's no logic to predict them — you make decisions but do homework, you have strong coffee but heavy rain. They must be learned as chunks, not deduced from rules.

Vocabulary for C1/Advanced

  • Low-frequency precision: mitigate, exacerbate, circumvent, undermine
  • Register control: begin (neutral) / commence (formal) / kick off (informal)
  • Academic discourse: notwithstanding, hitherto, whereby, insofar as
  • Sophisticated idioms: a double-edged sword, the tip of the iceberg, a foregone conclusion

C1 vocabulary = ~6,000–10,000 words. Low-frequency academic verbs, full register sensitivity, sophisticated idioms, precise discourse markers. The level where you sound like an educated native writer.

Focus: the rare verbs that make academic writing precise (elucidate, corroborate, exacerbate), and knowing WHEN each register is appropriate.

C1 | Advanced

  • Not only did she finish early, but she also helped others. — inversion for emphasis
  • It is the process that matters, not the result. — cleft sentence
  • I insist that he be present. — formal subjunctive
  • Were I to disagree, I would say so. — inverted conditional

These are C1 structures — the CEFR advanced level. At C1 you control inversion, cleft sentences, subjunctive forms, and register-switching fluently across formal and informal contexts.

Marker: if you can restructure a sentence for rhetorical effect without hesitation, you're C1.

Medium

  • If I were you, I would apologise. — one rule (second conditional), but distractors like was tempt you
  • Answers require active thought, not instant pattern recognition
  • Vocabulary and context are realistic, not artificially simplified
  • Usually tests one rule, but the wrong answers are plausible

Medium marks middle-difficulty challenges: A2B1, one rule tested, but with realistic distractors that require genuine understanding.

Use "Medium" when Easy feels too obvious but Hard feels overwhelming. This is where most productive learning happens — the sweet spot of difficulty.