Select ALL the grammatically correct ways the barista can ask the overly enthusiastic customer to stop.
Excuse me, sir! ______ on the espresso machine glass? It startles the baristas.

The correct answers are Would you mind not tapping and Could you please not tap.

To make a negative polite request, place "not" directly before the main verb.

  • Would you mind + not + verb-ing (not tapping)
  • Could you (please) + not + base verb (not tap)
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Modal verb

  • She can swim. — ❌ She can to swim. (modal + bare infinitive, no to)
  • You must leave now. — strong obligation
  • It might rain. — possibility (~50%)
  • He should apologise. — advice/recommendation

Modal verbs (can, could, may, might, must, shall, should, will, would) are auxiliaries expressing ability, permission, possibility, obligation, or speculation. Always + bare infinitive. Never inflected (she can, not she cans).

Rule: modals never take to after them, never add -s for third person, and can't combine directly (must can ❌ — use must be able to).

Negation

  • I don't see anything. — ❌ I don't see nothing. (double negative in standard English)
  • She never goes out.never already negates (no doesn't needed)
  • He doesn't like coffee. — do-support for negation
  • Nobody came. — negative subject (no auxiliary needed)

Negation uses not after an auxiliary/modal, or do-support when there's no auxiliary. One negative per clause in standard English — never, nobody, nothing already negate without adding not.

Rule: one negative element per clause. I don't see anything or I see nothing — never both together in standard English.

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.

Questions

  • Do you like coffee? — do-support (no existing auxiliary)
  • Can she swim? — inversion (auxiliary before subject)
  • Where does he live? — wh-question
  • You're coming, aren't you? — tag question

Questions require inversion (auxiliary before subject) or do-support (add do/does/did). Types: yes/no (Do you…?), wh- (What/Where/When…?), negative (Don't you…?), tag (…isn't it?).

Rule: find the auxiliary. Move it before the subject. No auxiliary? Add do/does/did. Never use just intonation in written English (You like coffee? is not standard).

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.

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.