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Chloe is frantically texting her best friend about the absolute tragedy of her ruined prom dress.
Select ALL the sentences that correctly use an adverb clause of reason without any grammatical errors.

The correct answers are: I am crying because my cat slept on my silk dress. Since my cat completely ruined the fabric, I have nothing to wear.

Adverb clauses of reason must start with a subordinating conjunction (like because, since, or as) and be followed by a complete clause (a subject and a verb).

"Because of" and "due to" are prepositions. They must be followed by a noun phrase (e.g., because of my cat), not a full clause with a verb like "ruined".

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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.

Conjunction

  • I was tired, but I stayed. — coordinating (links two equal clauses)
  • I stayed because I was needed. — subordinating (introduces dependent clause)
  • Although it rained, we went out. — subordinating (front position)
  • I was tired, because. — incomplete (subordinating conjunction needs a clause after it)

Conjunctions connect words, phrases, or clauses. Coordinating (and, but, or, so, yet, for, nor) join equals; subordinating (because, although, if, when, while) introduce dependent clauses.

Pattern: coordinating = equal partners, same grammatical weight. Subordinating = one clause depends on the other for its meaning.

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.

Preposition

  • interested in — ❌ interested on
  • good at football — ❌ good in football
  • depend on — ❌ depend of
  • arrive at the station — ❌ arrive to the station

Prepositions link nouns to the rest of the sentence: time (at 5pm), place (in London), manner (with care), abstract (afraid of). Most are idiomatic — the "correct" preposition must be memorised with each verb/adjective combination.

Rule: there is no universal rule. English prepositions are learned by combination: interested IN, good AT, depend ON, afraid OF. Your native language's equivalent will often mislead.

B1 | Intermediate

  • If I had more time, I would travel more. — second conditional
  • The bridge was built in 1920. — passive voice
  • She said she was tired. — reported speech with backshift
  • Although it rained, we enjoyed the trip. — complex sentence with concession

These are B1 patterns — the CEFR intermediate level. At B1 you link ideas, use passive voice, handle reported speech, and manage second conditional — enough for travel, work basics, and everyday independence.

Marker: if you can explain why something happened and follow a news story, you're B1.

Medium

  • If I were you, I would apologise. — one rule (second conditional), but distractors like was tempt you
  • Answers require active thought, not instant pattern recognition
  • Vocabulary and context are realistic, not artificially simplified
  • Usually tests one rule, but the wrong answers are plausible

Medium marks middle-difficulty challenges: A2B1, one rule tested, but with realistic distractors that require genuine understanding.

Use "Medium" when Easy feels too obvious but Hard feels overwhelming. This is where most productive learning happens — the sweet spot of difficulty.