20%
Read the secret agent's debriefing report about her latest mission. Select ALL the sentences that are grammatically correct.

The correct answers are: No sooner had the helicopter landed than the villain deployed the laser-equipped sharks. Hardly had the agent deactivated the bomb when the facility's alarm started blaring. Not until the smoke finally cleared did we realize the priceless diamond was missing.

Explanation of Correct Answers:

  • No sooner pairs with than and requires inversion (had the helicopter landed).
  • Hardly pairs with when and requires inversion (had the agent deactivated).
  • With Not until, the inversion happens in the main clause, not the "until" clause (did we realize).

Explanation of Incorrect Answers:

  • Scarcely... than is incorrect. Scarcely must be paired with when or before, not than.
  • Only later we discovered... is incorrect because it lacks inversion. When Only + time expression starts a sentence, the main clause must be inverted: "Only later did we discover..."
To ChallengesPreviousNext

Inversion

Inversion is reversing the normal English word order of subject + verb. The everyday case is subject–auxiliary inversion for questions: Sam has read itHas Sam read it?. The more advanced case is inversion after fronted negative or restrictive expressions: Rarely have I seen such dedication / Not only does she sing, she also writes.

The advanced kind is a hallmark of formal and literary English — used after openers like never, seldom, not until, only when, little did I know. Mastering it is a C1+ skill that signals careful, register-appropriate writing.

Adverb

An adverb modifies a verb, an adjective, or another adverb — adding information about how, when, where, how often, or to what degree something happens: she sings beautifully, unbelievably fast, we go there often. Many adverbs end in -ly, but plenty don't (well, fast, hard, almost).

Adverbs matter because they're how you add nuance without piling on extra clauses. Used well, a single adverb can sharpen a vague sentence (she answeredshe answered honestly), but misplace one and the meaning drifts in a way native speakers immediately notice.

Word Order

Word order is the sequence in which words appear in a sentence. English is fundamentally an SVO language — subject, verb, object (Kate loves Mark). The order of adjectives, adverbs, and modifiers within a noun phrase also follows fixed patterns (a small red wooden box, not a wooden red small box).

In English, word order carries grammatical meaning — change the order and you change the sentence. The dog bit the man and The man bit the dog differ only in word order, but the meaning flips entirely.

Negation

Negation in English usually places not after the auxiliary or modal verb: I am not going, She does not know, You must not go. When there's no auxiliary, you add do-support: I goI do not go. Most combinations contract: don't, can't, won't, isn't.

The trickiest rule for many learners: double negatives are not standard English. I didn't see nothing is non-standard; the standard forms are I saw nothing or I didn't see anything. Negative words like never, nobody, nothing already carry the negation — adding not on top doubles up.

Clause

A clause is a grammatical unit built around a verb — typically a subject plus a predicate (She laughed; The manager approved the budget). Clauses come in two types: independent clauses stand alone as complete sentences; dependent clauses need an independent clause to make sense (Because I overslept — incomplete on its own).

Spotting clause boundaries is the foundation of correct punctuation. Once you can see where one clause ends and another begins, comma rules, run-on sentences, and complex sentence structure stop being mysteries.

B2 | Upper Intermediate

B2 is the upper-intermediate level in the CEFR framework, sitting between B1 and C1. At B2 you can read editorials, follow most TED talks without subtitles, and hold extended conversations on abstract topics — including topics outside your everyday life.

Grammatically, B2 means flexible control of mixed conditionals, passive voice across tenses, reported speech with proper backshifting, and participle clauses. B2 is the standard target for university entrance exams (IELTS 5.5–6.5, TOEFL 87–109) and most skilled-migration thresholds — knowing whether you're there shapes your study plan.

Difficulty: Hard

The Hard difficulty tag marks questions and challenges aimed at upper-intermediate to advanced learners — typically B2 and above. Expect interacting rules, edge cases, distractors that look right at first glance, and contexts where the surface meaning and the grammatical answer don't match.

Filter by Hard when you're past the basics and want material that genuinely tests your understanding. These questions catch the gaps your textbook didn't — register-sensitive choices, exception cases, mixed conditionals, the difference between would have been and had been.