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Help a frustrated student complete a text message complaining about the noise next door. Select ALL the options that grammatically complete the sentence.
Through the thin walls, I heard my roommate's terrible band ___ the exact same song for three hours!

The correct answers are play and playing.

After verbs of perception (like hear, see, watch, feel), we can use an object followed by either a bare infinitive (play) or an -ing form/gerund (playing).

We never use the to-infinitive (to play) after an active verb of perception!

Note on meaning: Using "play" (bare infinitive) suggests you heard the entire completed action from start to finish. Using "playing" (-ing form) emphasizes the ongoing, continuous nature of the action. Both are completely correct here!

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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.

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.

Participle

  • a broken window — past participle as adjective
  • the running water — present participle as adjective
  • I have eaten. — past participle in perfect tense
  • She is sleeping. — present participle in progressive tense
  • I have went. — wrong (past tense, not past participle: use gone)

A participle is a verb form that also works as an adjective. Present (-ing): running, sleeping. Past (-ed or irregular): broken, written, gone. Used in progressive tenses, perfect tenses, passive voice, and as modifiers.

Trap: don't confuse past tense (went) with past participle (gone). After have/has/had → always past participle.

Object

  • Sam fed the dogs. — direct object (what was fed)
  • She sent him a present. — indirect object (who received it)
  • She waited for Lucy. — prepositional object (after preposition)
  • I gave her a book. — indirect + direct object together

An object is what a verb acts on or directs its action toward. Direct = the thing affected. Indirect = the recipient. Prepositional = after a preposition.

Test: Verb + what/whom? = direct object. Verb + to/for whom? = indirect object. After a preposition? = prepositional object.

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.