The correct answers are The aliens are expected to arrive on Earth next Tuesday. and It is expected that the aliens will arrive on Earth next Tuesday.
For future expectations, the personal passive structure uses the subject + passive verb + simple infinitive (The aliens are expected to arrive).
The impersonal passive structure uses "It" + passive verb + "that" clause with a future tense (It is expected that the aliens will arrive).
You cannot follow a personal subject like "The aliens" with a "that" clause in this structure, nor can you follow the impersonal "It is expected" directly with an infinitive phrase.
Passive voice
If your writing has been called "weak" or "evasive" — Mistakes were made, It was decided that... — you've hit the passive voice's main pitfall. Used deliberately, the passive is precise and useful: it foregrounds the action when the doer doesn't matter. Used by default, it makes prose feel like nobody's responsible for anything.
The passive voice is formed with be + past participle and turns the object into the subject: The chef cooked the meal → The meal was cooked (by the chef). Useful when the action matters more than the doer; overused, it makes writing feel evasive.
Infinitive
If you've ever written I enjoy to swim or He let me to go and only later learned why both are wrong — you've hit the infinitive's main puzzle. English is fussy: some verbs demand the to-infinitive, some demand the bare infinitive, some demand the gerund, and a few accept multiple options with different meanings (remember to lock vs remember locking).
The infinitive is the basic form of a verb, used non-finitely. The to-infinitive (to go) follows verbs like want, decide, plan; the bare infinitive (go) follows modal verbs (can, will) and causatives (Let him go).
Clause
If you've ever been told your sentence is a "run-on" or that you've used a comma where there should be a semicolon — you've hit the limits of writing without seeing clauses. Get this concept solid and most punctuation problems quietly disappear: you can finally tell a complete thought from a fragment without guessing.
A clause is a grammatical unit built around a verb, usually with a subject and a predicate. Independent clauses stand alone (I missed the bus); dependent clauses can't (Because I overslept). Combine them and you build complex sentences.
Future tense
If you've ever wondered why a native speaker said I'm meeting her tomorrow instead of I will meet her tomorrow — you've felt the future-tense puzzle. English has at least four common ways to talk about the future, and they're not interchangeable. Pick the wrong one and you sound either unnaturally formal or surprisingly vague about your own plans.
English uses several constructions for future time: will + infinitive (predictions, spontaneous decisions: I'll call), be going to (planned intentions, evidence-based predictions: It's going to rain), the present continuous for arrangements (I'm meeting Sam at six), and the present simple for fixed schedules (The train leaves at 8).
Indirect speech
If you've ever tried to retell what someone said and ended up with a verb-tense mess (She said she will come — wait, would come?), you've hit indirect speech. The rules look intricate but reduce to one move: when the reporting verb is past, shift everything in the reported clause one step into the past. Master that and reporting other people's words stops being a guessing game.
Indirect speech reports what someone said without quoting them: "I like apples" → He said that he liked apples. The core mechanism is backshift — tenses retreat one step into the past — plus pronoun and time-expression shifts.
B2 | Upper Intermediate
If a university admissions team or visa office has ever asked you for an English test score, B2 is probably the level they had in mind. It's the threshold where your English stops being a constraint and starts being a tool — and the line between B1 and B2 is often the line between "stuck in beginner classes" and "ready to study or work in English."
B2 is the upper-intermediate level in the CEFR framework, demanding flexible control of mixed conditionals, passive voice across tenses, reported speech with backshifting, and participle clauses.
Difficulty: Hard
If easy and medium questions are clicking but you still feel exposed in real conversation or formal writing, you've outgrown the basics. Hard material is where the gaps you didn't know you had show up: the distractor that "sounds right", the rule that interacts with another rule, the case where context changes the answer. It's where genuine fluency is built.
The Hard difficulty tag marks upper-intermediate to advanced challenges — typically B2 and above. Interacting rules, edge cases, plausible distractors, and contexts that require genuine understanding rather than surface pattern-matching.