The correct answers are Had we not lost, If we had not lost, and If we hadn't lost.
This is a third conditional sentence describing an unreal past situation.
You can use the standard "if" clause (If we had not lost / If we hadn't lost).
You can also invert the subject and auxiliary verb to sound more formal (Had we not lost).
However, in inverted negative conditionals, the word "not" must follow the subject. Contracted negative inversions like "Hadn't we lost" are grammatically incorrect!
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.
Inversion
Inversion is reversing the normal English word order of subject + verb. The everyday case is subject–auxiliary inversion for questions: Sam has read it → Has Sam read it?. The more advanced case is inversion after fronted negative or restrictive expressions: Rarely have I seen such dedication / Not only does she sing, she also writes.
The advanced kind is a hallmark of formal and literary English — used after openers like never, seldom, not until, only when, little did I know. Mastering it is a C1+ skill that signals careful, register-appropriate writing.
Negation
Negation in English usually places not after the auxiliary or modal verb: I am not going, She does not know, You must not go. When there's no auxiliary, you add do-support: I go → I do not go. Most combinations contract: don't, can't, won't, isn't.
The trickiest rule for many learners: double negatives are not standard English. I didn't see nothing is non-standard; the standard forms are I saw nothing or I didn't see anything. Negative words like never, nobody, nothing already carry the negation — adding not on top doubles up.
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.
Word Order
Word order is the sequence in which words appear in a sentence. English is fundamentally an SVO language — subject, verb, object (Kate loves Mark). The order of adjectives, adverbs, and modifiers within a noun phrase also follows fixed patterns (a small red wooden box, not a wooden red small box).
In English, word order carries grammatical meaning — change the order and you change the sentence. The dog bit the man and The man bit the dog differ only in word order, but the meaning flips entirely.
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.