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Complete the museum tour guide's very important safety instruction.

The nervous tour guide warned the school children _____ the priceless dinosaur bones.

The correct answer is not to touch.

The reporting verb "warn" follows the pattern: warn + object + (not) + to + infinitive. When making it negative, we place "not" right before the infinitive.

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Indirect speech

If you've ever tried to retell what someone said and ended up with a verb-tense mess (She said she will come — wait, would come?), you've hit indirect speech. The rules look intricate but reduce to one move: when the reporting verb is past, shift everything in the reported clause one step into the past. Master that and reporting other people's words stops being a guessing game.

Indirect speech reports what someone said without quoting them: "I like apples"He said that he liked apples. The core mechanism is backshift — tenses retreat one step into the past — plus pronoun and time-expression shifts.

Verb

If grammar feels overwhelming, the fix is almost always to focus on verbs first. They carry the action, the time, the mood, and the voice — a single verb form decides whether your sentence reads as past or present, fact or hypothetical, active or passive. Get verbs solid and the rest of grammar suddenly looks much smaller.

A verb expresses action, state, or occurrence — the engine of every English sentence. Most verbs have five forms (base, -s, past tense, past participle, -ing); be has eight; modal verbs have fewer. Verbs carry tense, aspect, mood, and voice.

Infinitive

If you've ever written I enjoy to swim or He let me to go and only later learned why both are wrong — you've hit the infinitive's main puzzle. English is fussy: some verbs demand the to-infinitive, some demand the bare infinitive, some demand the gerund, and a few accept multiple options with different meanings (remember to lock vs remember locking).

The infinitive is the basic form of a verb, used non-finitely. The to-infinitive (to go) follows verbs like want, decide, plan; the bare infinitive (go) follows modal verbs (can, will) and causatives (Let him go).

Negation

If your native language uses double negatives (I don't see nothing) — like Russian, Spanish, or French — you've probably been told this is wrong in English and not been entirely sure what the fix is. Standard English uses one negative per clause: either I saw nothing or I didn't see anything, never both. Once you internalise that single rule, your written English clears up a lot.

Negation in English uses not after an auxiliary or modal verb: I am not going. Without an auxiliary, you add do-support (I do not go). Negative words like never and nobody already negate the clause — adding not on top creates non-standard double negatives.

B1 | Intermediate

If you can hold a conversation about your weekend, explain why you're late, and follow a short news story without panicking — but still feel lost in fast or technical English — you're probably operating at B1. Knowing this matters: study material at the wrong level either bores you or burns you out, and B1 is the typical target for travel, casual work, and most everyday social English.

B1 is the intermediate level in the CEFR framework, where you handle everyday English independently and start combining ideas with complex sentences, passive voice, and modal verbs.

Difficulty: Medium

If easy questions feel too obvious but hard questions leave you guessing, you're probably ready for Medium — the level where most real learning happens. It pushes just enough to expose the rules you don't quite have yet, without burying you in edge cases. This is where steady fluency is built, one well-aimed challenge at a time.

The Medium difficulty tag marks middle-range challenges — typically A2 to B1. One rule per question, realistic distractors, and contexts that require active thought rather than instant recognition.