Drag the correct verb forms to help the exhausted detective finish his stakeout report for the chief.
If the suspect doesn't show up by midnight, we will have been sitting in this freezing unmarked van for twelve hours. At that point, my partner will have been complaining about his cold feet for exactly eleven of those hours!
If the suspect doesn't show up by midnight, we will have been sitting in this freezing unmarked van for twelve hours.
The future perfect continuous is required here because we are calculating the duration of an ongoing action ("for twelve hours") up to a specific future moment ("by midnight"). "Will be sitting" describes an action happening at a future time, but fails to capture the accumulated duration.
At that point, my partner will have been complaining about his cold feet for exactly eleven of those hours!
Because "complaining" is an ongoing, continuous action rather than a single completed event, the continuous form (will have been complaining) is much more natural and accurate here than the simple perfect (will have complained).
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.
Future tense
English doesn't have a single dedicated future tense — it has multiple ways to talk about future time. The most common are will + bare infinitive (I'll call you), be going to + infinitive (I'm going to study), the present continuous for arrangements (I'm meeting Sam at six), and the present simple for fixed schedules (The train leaves at 8).
The choice between them isn't free — each carries a different shade of meaning. Will often signals spontaneous decisions or pure prediction; going to signals intentions formed earlier or evidence-based predictions. Picking the right form is one of the trickiest distinctions for B1+ learners.
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.
Progressive tense
The progressive aspect (also called continuous) marks an action as ongoing at the time of reference, formed with be + present participle (-ing): I am working, She was reading, They will be travelling. It signals temporary or in-progress events — the contrast with the simple aspect (I work = habit; I'm working = right now) is one of the most-used distinctions in English.
Some verbs (stative verbs like know, believe, own, belong) don't normally take the progressive — I'm knowing the answer sounds wrong. Recognising stative vs dynamic verbs is what stops you from over-applying the rule.
Conditional sentence
A conditional sentence describes one situation as depending on another. It pairs a condition clause (usually starting with if) with a consequence clause: If it rains, we'll stay in. The condition can refer to general truths, real future possibilities, hypothetical present situations, or unreal past situations — and each type uses a specific tense pattern.
English teaching groups these into zero, first, second, third, and mixed conditionals. Mastering them lets you talk about plans, regrets, hypotheticals, and warnings — territory you can't reach with simple present and past tenses alone.
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: Hard
The Hard difficulty tag marks questions and challenges aimed at upper-intermediate to advanced learners — typically B2 and above. Expect interacting rules, edge cases, distractors that look right at first glance, and contexts where the surface meaning and the grammatical answer don't match.
Filter by Hard when you're past the basics and want material that genuinely tests your understanding. These questions catch the gaps your textbook didn't — register-sensitive choices, exception cases, mixed conditionals, the difference between would have been and had been.