Help the exhausted detective summarize a dead-end case to her partner.
The suspect has a rock-solid alibi backed by security footage. _______ him further without finding new evidence.
The correct answer is There's no point in interrogating.
In English, the correct fixed expressions are "there's no point in [doing something]" and "it's no use [doing something]." The distractors mix up these phrases by using the wrong dummy subject ("it" vs. "there"), the wrong preposition, or an infinitive verb instead of a gerund.
Gerund
If you've ever said I enjoy to read or good at to swim and wondered why it sounded wrong, you've met the gerund. English is fussy about which structures take -ing and which take to + verb, and getting this wrong is one of the most common giveaways that someone learned grammar from a list rather than from real usage.
A gerund is the -ing form of a verb acting as a noun — reading, swimming, being late. After many common verbs (enjoy, avoid, finish) and after every preposition, English demands the gerund, never the infinitive.
Phrase
If you've ever read a long sentence in English and felt lost in the middle, you've hit a sentence with too many phrases stacked together. Learning to spot phrases — on the table, the man with the hat, very quickly — turns dense prose into something you can parse: each phrase is one chunk of meaning, not a string of unrelated words.
A phrase is a group of words functioning as a single unit in a sentence, without a subject + verb pair (which would make it a clause). Types include noun phrase (the red car), verb phrase (has been running), prepositional phrase (on the table), and adjective/adverb phrases.
Subject
If you've ever written The list of items are wrong (should be is wrong) — you've hit the subject-agreement trap. The subject is list, not items, and the verb has to agree with it. Long sentences with prepositional phrases between the subject and verb are where this most often goes wrong, and getting it right is what stops careful readers from flagging your writing.
The subject is the part of a sentence or clause that says who or what the sentence is about. Typically a noun, pronoun, or noun phrase before the verb, controlling the verb's number and person.
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).
Collocations
If your English vocabulary is large but your speech still sounds slightly off — do a mistake, powerful coffee, high winds blew strongly — you've hit the collocation problem. Each word is correct in isolation, but native speakers don't pair them that way. Fixing it isn't about more vocabulary; it's about learning words in their natural company.
Collocations are word combinations that habitually occur together: make a decision, strong coffee, heavy rain, highly unlikely. The grammar permits other pairings, but fluent English consistently chooses one over the rest. They're the connective tissue of natural-sounding language.
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: Hard
If easy and medium questions are clicking but you still feel exposed in real conversation or formal writing, you've outgrown the basics. Hard material is where the gaps you didn't know you had show up: the distractor that "sounds right", the rule that interacts with another rule, the case where context changes the answer. It's where genuine fluency is built.
The Hard difficulty tag marks upper-intermediate to advanced challenges — typically B2 and above. Interacting rules, edge cases, plausible distractors, and contexts that require genuine understanding rather than surface pattern-matching.