The correct answers are widely accepted, widely believed, and widely recognized.
Widely means "by a lot of people" or "in a lot of places," making it perfect for academic consensus (accepted, believed, recognized).
"Convinced" applies to people having a firm belief, but we don't say "it is widely convinced" (we say "many scientists are firmly convinced"). "Undeniable" is an absolute adjective that doesn't pair with "widely"; we would say it is absolutely undeniable.
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 answered → she answered honestly), but misplace one and the meaning drifts in a way native speakers immediately notice.
Adjective
An adjective is a word that describes a noun or pronoun — giving more information about its quality, state, or identity. Adjectives sit either before the noun (a tall building) or after a linking verb (The soup is hot), and they answer questions like what kind?, which one?, or how many?
Getting adjectives right matters for two everyday reasons: their position is fixed (you can't say a redly dress), and when you stack several before a noun, English follows a strict order — opinion, then size, then age, then colour. Break that order and the sentence sounds off even when each word is correct.
Participle
A participle is a verb form that doubles as an adjective or adverb. English has two: the present participle ending in -ing (running, sitting) and the past participle (broken, gone, written). Both build tenses (is running, has gone), but they also stand alone modifying nouns (the broken window) or verbs (Exhausted, we fell asleep).
Participles look like simple parts of speech but pull double duty — most learner errors come from confusing the present participle with the gerund (also -ing but acting as a noun) or the past participle with the past tense.
Passive voice
The passive voice flips a sentence so the object of the action becomes the subject, and the original doer either disappears or moves to a by-phrase: The chef cooked the meal (active) → The meal was cooked by the chef (passive). Formed with be + past participle (was cooked, is being written, had been seen), and works across all tenses.
Use the passive when the action matters more than the doer (The report was filed), when the doer is unknown or obvious (My car was stolen), or to soften criticism (Mistakes were made). Overusing it makes prose feel evasive — careful writers reach for the active voice by default.
Collocations
Collocations are combinations of words that habitually occur together in a fixed order — make a decision (not do a decision), strong coffee (not powerful coffee), heavy rain (not thick rain). The grammar would allow either pairing, but native speakers consistently pick one and reject the other. Common patterns include verb + noun, adjective + noun, adverb + adjective, and adverb + verb.
Learning vocabulary as collocations rather than isolated words is the single fastest way to sound natural in English. It's the difference between I made a big mistake and I did a big mistake — small, but immediately noticeable.
Vocabulary for B2/Upper Intermediate
The B2 vocabulary tag covers vocabulary for upper-intermediate English — roughly 4,000–6,000 words. New territory: specialised fields (business, science, technology basics), nuanced emotions, hedging language (tend to, seem like, appear), reporting verbs (claim, suggest, imply), and a much wider range of idioms and figurative expressions.
B2 is the level where you can read newspaper editorials, follow professional meetings, and argue a position with subtlety. Vocabulary work at this stage is less about quantity and more about precision.
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: Medium
The Medium difficulty tag marks questions and challenges in the middle of the difficulty range — typically suitable for A2 to B1 learners. Expect a single rule with realistic distractors, longer sentences, and contexts where you have to think before answering rather than reading off the obvious choice.
Filter by Medium when you're past the absolute basics and ready to consolidate. It's the level where most lasting progress happens — easy enough that you can finish without exhausting concentration, hard enough that getting it right means you've actually understood.