Complete the starship captain's slightly panicked log entry about Planet Zog by selecting the correct options.
The mysterious alien artifacts _________________________ near the landing zone have started glowing neon green. Any crew members _________________________ sudden urges to sing opera must report to the medical bay immediately. The engine repairs currently _________________________ on the outer hull are absolutely critical for our escape.

The mysterious alien artifacts found near the landing zone have started glowing neon green.

Use the past participle to reduce a simple passive relative clause ("artifacts which were found").

Any crew members experiencing sudden urges to sing opera must report to the medical bay immediately.

Use the present participle to reduce an active relative clause ("crew members who are experiencing").

The engine repairs currently being done on the outer hull are absolutely critical for our escape.

To reduce a continuous passive relative clause ("repairs which are currently being done"), use being + the past participle. Just using "done" would imply the repairs are already finished, which contradicts the word "currently."

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Relative clause

  • The man who called is my uncle. — restrictive (essential: which man?)
  • My uncle, who lives in Paris, called. — non-restrictive (extra info, commas)
  • My uncle that lives in Paris — wrong (that can't introduce non-restrictive)
  • The book that I read = The book I read — restrictive (pronoun optional)

Relative clauses modify nouns using who/whom/whose/which/that or where/when/why. Restrictive = essential, no commas, that OK. Non-restrictive = extra, needs commas, uses which/who (never that).

Rule: if you can remove the clause and still know which noun is meant → non-restrictive (commas). If removing it makes the noun ambiguous → restrictive (no commas).

Participle

  • a broken window — past participle as adjective
  • the running water — present participle as adjective
  • I have eaten. — past participle in perfect tense
  • She is sleeping. — present participle in progressive tense
  • I have went. — wrong (past tense, not past participle: use gone)

A participle is a verb form that also works as an adjective. Present (-ing): running, sleeping. Past (-ed or irregular): broken, written, gone. Used in progressive tenses, perfect tenses, passive voice, and as modifiers.

Trap: don't confuse past tense (went) with past participle (gone). After have/has/had → always past participle.

Passive voice

  • The meal was cooked by the chef. — passive (action matters)
  • Mistakes were made. — passive, agent hidden (evasive)
  • ✅ Active: The chef cooked the meal. — stronger, clearer
  • The report was being been written. — malformed passive

The passive = be + past participle. Object becomes subject. Use it when the doer is unknown, irrelevant, or obvious. Avoid when it hides responsibility or weakens prose.

Formula: find the active object → make it the subject → use be (matching tense) + past participle → optionally add by + agent.

Complex sentence

  • Because I overslept, I missed the bus. — dependent clause (reason) + independent
  • The man who called is my uncle. — relative clause inside the sentence
  • If it rains, we'll stay inside. — conditional dependent + independent
  • Because I overslept. — fragment (dependent clause alone)

A complex sentence pairs an independent clause with one or more dependent clauses linked by subordinating conjunctions (because, although, if, when) or relative pronouns (who, which, that).

Pattern: independent clause = the main point. Dependent clause = the background, reason, or condition. Move the dependent clause around for emphasis.

Clause

  • I missed the bus. — ✅ independent clause (stands alone)
  • Because I overslept. — ❌ fragment (dependent clause, can't stand alone)
  • Because I overslept, I missed the bus. — ✅ dependent + independent = complete sentence
  • I missed the bus, and I was late. — ✅ two independent clauses joined by and

A clause is a unit built around a verb with a subject. Independent = can stand alone. Dependent = needs an independent clause to complete it.

Test: does the group of words have a subject + verb AND can it be a sentence on its own? Yes → independent clause. Has a subject + verb but feels incomplete → dependent clause.

B2 | Upper Intermediate

  • If I had studied harder, I would have passed. — third conditional
  • The report is being reviewed by the committee. — passive progressive
  • Having finished the exam, she left. — participle clause
  • He denied having taken the money. — complex verb pattern

These are B2 patterns — the CEFR upper-intermediate level. At B2 you handle mixed conditionals, all passive forms, participle clauses, and can argue a point clearly. This is the level most universities and employers require.

Marker: if you can write a structured essay and debate an abstract topic, you're B2.

Hard

  • Had she not intervened, the situation would have escalated. — inverted conditional
  • All distractors are grammatically plausible in other contexts
  • Multiple rules interact (e.g., tense + aspect + modality)
  • Context determines the answer — no single "rule" is enough

Hard marks upper-intermediate to advanced challenges: B2+, interacting rules, edge cases, plausible distractors, and contexts where pattern-matching fails.

Use "Hard" when Easy/Medium feel trivial and you want to test whether you actually understand a rule versus just recognising surface patterns.