30%
Choose the correct sentence(s).
  1. Correct. Even though links the two sentences and creates an adverbial of concession.
  2. Incorrect. There are two independent clauses here that are not linked in any way. The comma is not enough to indicate a relationship - there is information missing. Even if you read the two as seperate sentences, it has stopped making sense (if he was so careful, why was his knee sore?).
  3. The sentence starts with although..., creating the adverbial (subordinate) clause of concession. The comma separates from the ordinary clause that it relates to: his knee was really sore after the performance.
  4. Very careful had been the dancer has incorrect word order; the dancer is the subject and it should go before the verbs had been and adjective very careful. It also misses a link between the two sentences, so this is incorrect in many ways.
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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.

Adverb

  • She sings beautifully — ❌ She sings beautiful
  • He drives carefully — ❌ He drives careful
  • They arrived late — ✅ a late train (same form, both roles)
  • She works hard — ❌ She works hardly (different meaning!)

The -ly words are adverbs — they modify verbs, adjectives, or other adverbs, telling you how, when, where, or to what degree.

Pattern: most adjectives become adverbs by adding -ly, but watch the exceptions — fast, hard, late, well — that keep the same shape or change meaning entirely.

Dependent clause

  • Because I was tired. — fragment (dependent clause standing alone)
  • I left early because I was tired. — attached to independent clause
  • The man who called is my uncle. — relative clause (modifies man)
  • If you're ready, let's go. — conditional dependent clause

A dependent clause has a subject + verb but cannot be a complete sentence. It starts with a subordinating word (because, if, when, although, who, which) and must attach to an independent clause.

Test: does the clause start with a subordinator and feel incomplete on its own? → dependent clause. On its own, it's a fragment — attach it to a main clause.

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.

C1 | Advanced

  • Not only did she finish early, but she also helped others. — inversion for emphasis
  • It is the process that matters, not the result. — cleft sentence
  • I insist that he be present. — formal subjunctive
  • Were I to disagree, I would say so. — inverted conditional

These are C1 structures — the CEFR advanced level. At C1 you control inversion, cleft sentences, subjunctive forms, and register-switching fluently across formal and informal contexts.

Marker: if you can restructure a sentence for rhetorical effect without hesitation, you're C1.

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.