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Drag the correct words to complete these sentences. Pay attention to the difference between past habits and being accustomed to something!

Context: Carlos is comparing his old life in Spain with his new routine in Canada.

"In Spain, I used to wake up at 10 a.m. (That was my habit back then!) Now in Canada, I am used to waking up at 6 a.m. for work. (I'm accustomed to it now!)"

The first blank is used to.

Used to + base verb describes a past habit that no longer exists. The second blank is wake. After used to (past habit), use the base verb (no -ing, no "to"). The third blank is am used to. Be used to + gerund means "be accustomed to" something now. The fourth blank is waking. In be used to, the word to is a preposition, so it's followed by a gerund (-ing form).

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Gerund

  • I enjoy reading. — ❌ I enjoy to read.
  • She's good at swimming. — ❌ She's good at to swim.
  • He avoids making eye contact. — gerund after avoid
  • Running is good exercise. — gerund as subject

A gerund is the -ing form of a verb functioning as a noun. It follows verbs like enjoy, avoid, finish, mind and ALL prepositions. Never use an infinitive where a gerund is required.

Rule: after a preposition (at, in, of, about, without) → always gerund. After enjoy, avoid, finish, mind, suggest, deny → always gerund.

Infinitive

  • I want to go. — to-infinitive after want
  • She can swim. — bare infinitive after modal
  • Let me help. — bare infinitive after let
  • I enjoy to read. — wrong (enjoy takes gerund, not infinitive)

The infinitive has two forms: to-infinitive (to go) after verbs like want, decide, plan, hope; bare infinitive (go) after modals and causatives (let, make, help).

Rule: after want, need, decide, plan, hope, expect, agree, refuse → to-infinitive. After can, will, must, let, make → bare infinitive. After enjoy, avoid, finishgerund, NOT infinitive.

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.

B1 | Intermediate

  • If I had more time, I would travel more. — second conditional
  • The bridge was built in 1920. — passive voice
  • She said she was tired. — reported speech with backshift
  • Although it rained, we enjoyed the trip. — complex sentence with concession

These are B1 patterns — the CEFR intermediate level. At B1 you link ideas, use passive voice, handle reported speech, and manage second conditional — enough for travel, work basics, and everyday independence.

Marker: if you can explain why something happened and follow a news story, you're B1.

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.