The correct answers are affect, effect, affect, and effect.
"Affect" is typically a verb meaning "to influence" (temperatures influence migration). "Effect" is typically a noun meaning "result" (the result on polar bears). "Affect" is again the verb (pollution will influence ecosystems). "Effect" as a verb means "to bring about" or "to cause" — here, policies will bring about positive change. This is the trickiest usage!
Noun
A noun is a word that names something — a person, place, thing, idea, action, or quality. Nouns are one of the open word classes in English, alongside verbs, adjectives, and adverbs. They typically appear as the subject or object of a clause, after articles or adjectives, and as the head of a noun phrase.
Recognising nouns reliably is the foundation for nearly every other grammar topic — agreement, articles, plurals, possessives, and prepositions all depend on it. Get this right and the rest of English grammar starts to fall into place.
Verb
A verb is a word that expresses an action, a state, or an occurrence — the engine of every English sentence. Most verbs have five forms: base (go), -s form (goes), past tense (went), past participle (gone), and -ing form (going). The verb be is the major exception with eight forms; modal verbs like can and must have fewer.
Verbs carry tense (when), aspect (how it unfolds), mood (the speaker's attitude), and voice (active vs passive). Mastering them is foundational — virtually every other grammar topic depends on getting verbs right.
Vocabulary
The Vocabulary tag groups practice that focuses on words rather than grammar rules — common words, collocations, phrasal verbs, idioms, and the lexical patterns native speakers reach for instinctively. It cuts across grammar topics, offering targeted vocabulary work at every CEFR level from A1 to C2.
Grammar gets you the structure of English; vocabulary gets you the colour. Plenty of B1 grammar with A2 vocabulary still sounds simple; the right word at the right register is what shifts your English from "correct" to "natural".
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.