The correct answers are: The suspect locked himself inside the bank vault by accident. The mayor herself provided an ironclad alibi for the prime suspect. The criminal mastermind planned the entire operation by himself.
...locked himself... correctly uses a reflexive pronoun because the subject ("The suspect") and the object are the same.
The mayor herself... correctly uses an intensive pronoun to emphasize that it was the mayor, surprisingly, who provided the alibi.
...by himself. correctly uses the phrase meaning "alone."
Incorrect options:
"The fleeing thief took the stolen diamonds with himself" is incorrect. For prepositions indicating spatial relationships (like with, beside, behind), we use personal object pronouns, not reflexive ones. It should be with him.
"...hid ourself..." is incorrect. "Witnesses" is plural third-person, so the correct reflexive pronoun is themselves. Furthermore, "ourself" is not a standard word; the first-person plural is "ourselves."
Pronoun
If you've ever paused before who vs whom, its vs it's, or me vs I — you've felt how much weight pronouns carry in English. They're tiny words but they're case-sensitive (I vs me), context-dependent, and one of the few places where everyday English still trips careful speakers. Get the common patterns right and you instantly sound more careful.
A pronoun is a closed class of small words that replace nouns or noun phrases. Types: personal (I, you, he…), demonstrative (this, that), relative (who, which), interrogative (who?, what?), reflexive (myself), and indefinite (everyone, nobody).
Preposition
If you've ever written I'm interested on you (should be in) or I'm good on football (should be at) — you've hit prepositions' main pitfall. Their choice is mostly idiomatic, not logical, and rarely matches what your native language does. Memorising the right preposition for each common verb and adjective is what stops your speech from sounding subtly off.
A preposition is a small word linking a noun or noun phrase to other parts of the sentence: in, on, at, to, from, with. Marks time, place, manner, or abstract relationships. Choice is largely idiomatic, especially in fixed combinations (depend on, good at, afraid of).
English Grammar Basics
If grammar feels like a tangle of rules you can never quite remember, the fix isn't more advanced material — it's making the foundations automatic. The English Grammar Basics tag is where you do that: the building blocks every other topic stands on. Get these right and the rest stops feeling random.
It marks quizzes and explainers covering the core of English: nouns, verbs, adjectives, adverbs, prepositions, conjunctions, tenses, voice, mood, and basic sentence structure. Useful whether you're a beginner or refreshing rusty knowledge.
Humor
If you've ever reached the third drill of present perfect and felt your eyes glaze over, you've hit the limits of dry repetition. Practice that's even mildly funny is far easier to come back to — and far easier to remember weeks later. That's the whole point of the Humor tag.
The Humor tag marks questions where the author has tried to make the practice entertaining alongside instructive. Subjective, sometimes silly, but designed to keep you engaged long enough for the rule to stick.
B2 | Upper Intermediate
If a university admissions team or visa office has ever asked you for an English test score, B2 is probably the level they had in mind. It's the threshold where your English stops being a constraint and starts being a tool — and the line between B1 and B2 is often the line between "stuck in beginner classes" and "ready to study or work in English."
B2 is the upper-intermediate level in the CEFR framework, demanding flexible control of mixed conditionals, passive voice across tenses, reported speech with backshifting, and participle clauses.
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.