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.

Phrasal verb

• give up = quit — ≠ give + up literally
• come across = find by chance — ≠ come + across literally
• put up with = tolerate — 3-word phrasal verb
• look into = investigate — ≠ physically look inside something

Phrasal verbs = verb + particle/preposition forming a unit with non-literal meaning. There are thousands, and they dominate casual native English. They must be learned as whole units.

Key fact: the particle completely changes the verb's meaning. Look up (search), look after (care for), look into (investigate), look down on (disrespect) — all different.

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

• A1: ~500–800 words (survival: family, food, numbers)
• A2: ~1,500–2,500 (routine: work, leisure, basic phrasal verbs)
• B1: ~2,500–4,000 (opinions, news, abstract topics)
• B2: ~4,000–6,000 (register precision, hedging, idioms)
• C1: ~6,000–10,000 (academic, register sensitivity)
• C2: 10,000+ (literary, rare, full style range)

Vocabulary covers word-level practice: individual words, collocations, phrasal verbs, idioms. Organised by CEFR level. Grammar tells you HOW to build sentences; vocabulary gives you WHAT to put in them.

B2 | Upper Intermediate

• ✅ If I had studied harder, I would have passed. — third conditional
• ✅ The report is being reviewed by the committee. — passive progressive
• ✅ Having finished the exam, she left. — participle clause
• ✅ He denied having taken the money. — complex verb pattern

These are B2 patterns — the CEFR upper-intermediate level. At B2 you handle mixed conditionals, all passive forms, participle clauses, and can argue a point clearly. This is the level most universities and employers require.

Marker: if you can write a structured essay and debate an abstract topic, you're B2.

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: A2–B1, 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.