80%
Select correct verbs.
Olivia might _________________________ to the zoo tomorrow if the weather _________________________ nice

Olivia might go to the zoo tomorrow if the weather is nice.

First conditional with might. Use might + simple infinitive to indicate a remote possible outcome (It is likely Olivia will decide not to go, even if the weather is nice).

Olivia might go to the zoo tomorrow if the weather is nice.

The first conditional is formed by if + simple present verb, in this case is

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Conditional sentence

  • If you heat ice, it melts. — zero conditional (always true)
  • If it rains, I*'ll** take an umbrella.* — first conditional (real future)
  • If I had wings, I would fly. — second conditional (unreal present)
  • If I had left earlier, I would have caught the train. — third conditional (unreal past)

Conditional sentences pair an if-clause with a consequence. Five patterns (zero through mixed) each combine specific tenses to express different levels of reality and time.

Pattern: the tense in the if-clause is always one step "back" from what you'd expect — past for present hypotheticals, past perfect for past hypotheticals.

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).

Verb tense

SimpleProgressivePerfectPerfect Progressive
Pastworkedwas workinghad workedhad been working
Presentwork(s)am workinghave workedhave been working
Futurewill workwill be workingwill have workedwill have been working

Verb tense = time (past/present/future) × aspect (simple/progressive/perfect) = 12 forms. Each slot has a specific job — not just "when" but "how the action relates to its time frame."

Key insight: most learners don't need all 12 at once. Simple covers 80% of communication. Add perfect and progressive as needed.

Auxiliary verb

  • Do you know? — ❌ Know you? (English requires do-support for questions)
  • She has finished. — ❌ She finished has. (auxiliary before main verb)
  • They are leaving. — ❌ They leaving. (progressive needs be)
  • He doesn't smoke. — ❌ He smokes not. (negation needs do)

Auxiliary verbs (be, have, do, and the modals) combine with main verbs to build questions, negatives, tenses, aspects, and passive voice.

Pattern: if you need to ask a question, negate, or stack tense/aspect — you need an auxiliary. The main verb carries meaning; the auxiliary carries grammar.

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.

Hard

  • Had she not intervened, the situation would have escalated. — inverted conditional
  • All distractors are grammatically plausible in other contexts
  • Multiple rules interact (e.g., tense + aspect + modality)
  • Context determines the answer — no single "rule" is enough

Hard marks upper-intermediate to advanced challenges: B2+, interacting rules, edge cases, plausible distractors, and contexts where pattern-matching fails.

Use "Hard" when Easy/Medium feel trivial and you want to test whether you actually understand a rule versus just recognising surface patterns.