The suspect claimed that he had never seen that diamond.
When the reporting verb is in the past tense ("claimed"), the present perfect tense ("have seen") backshifts to the past perfect ("had seen").
Demonstrative pronouns also shift away from the speaker's original physical context. "This" becomes "that."
Indirect speech
Indirect speech (also called reported speech) is how you tell someone what another person said without quoting their exact words. "I like apples" → He said that he liked apples. The signature move is backshift: tenses move one step into the past when the reporting verb (said, told, thought) is itself in the past — present becomes past, past becomes past perfect, will becomes would, can becomes could.
Pronouns and time expressions also shift to fit the new perspective: "I'll see you tomorrow" → She said she'd see me the next day. Mastering this is essential for B1+ communication, especially in writing.
Perfect tense
The perfect aspect marks an action as complete relative to a point in time. It's formed with have + past participle: I have eaten (present perfect), She had finished (past perfect), They will have arrived (future perfect). The perfect doesn't just say when — it says the action's completion is relevant to the time of reference.
The trickiest English-specific use is the present perfect: I have lived in Paris connects the past to now (you may still live there), while I lived in Paris doesn't. This connection is one of the biggest jumps for learners whose native language doesn't make the same distinction.
Determiner
A determiner is a word that comes before a noun to clarify what it refers to: which one, how many, whose. The English determiners include articles (a, the), demonstratives (this, that), possessives (my, your), quantifiers (some, many, few), and distributives (each, every).
Most singular countable nouns in English require a determiner — I bought book is wrong; you need I bought a book or I bought the book. Determiner choice signals how much information you assume the listener already has, so getting it right shapes how natural your speech and writing sound.
Pronoun
A pronoun is a small, closed class of words that stands in for a noun or noun phrase. The main types: personal (I, you, he, she, it, we, they) plus their object (me, him) and possessive (my, mine) forms; demonstrative (this, that); relative (who, which, that); interrogative (who, what); and reflexive (myself, yourself).
Pronouns are how English avoids endlessly repeating names. The catch: their meaning depends entirely on context, so unclear pronoun reference (Tom told Mike that he was wrong — who's he?) is one of the most common writing problems.
Verb tense
Verb tense is the verb form that signals when the action happens. English has three time references — past, present, and future — combined with three aspects (simple, progressive, perfect, plus perfect progressive) to give twelve standard tense forms in total.
Each tense form carries specific meaning beyond just "when". I worked (simple past) and I have worked (present perfect) both refer to past action, but only the second connects that action to the present. Picking the right tense is what makes English narratives clear; the wrong one makes meaning subtly drift.
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.