The correct answers are What the elusive thief left behind was a single red rose. and The inspector will aggressively pursue whoever tampered with the evidence.
A nominal relative clause functions as a noun phrase (acting as a subject, object, etc.) and contains its own antecedent within the relative pronoun. "What" means "the thing that," and "whoever" means "the person who."
Incorrect options:
- "The single red rose that the thief left behind..." contains a standard relative clause modifying the head noun "rose."
- "The inspector asked what the elusive thief had left behind" contains an interrogative noun clause (an embedded question), not a nominal relative clause.
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).
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.
Sentence
- She left. — simple (one independent clause)
- She left, and he stayed. — compound (two independents)
- She left because she was tired. — complex (independent + dependent)
- She left because she was tired, and he stayed. — compound-complex
A sentence = one or more clauses forming a complete thought, ending with terminal punctuation. Four types based on clause structure: simple, compound, complex, compound-complex.
Minimum requirement: at least one independent clause with a subject + finite verb. Without that → fragment.
Noun
- The cat sat on the mat. — concrete nouns (things you can touch)
- Happiness is important. — abstract noun (idea/quality)
- London is beautiful. — proper noun (specific name, capitalised)
- I need some information. — uncountable noun (no a/an, no plural)
A noun names a person, place, thing, idea, or quality. Nouns determine article choice, verb agreement, and pronoun reference. Types: common/proper, concrete/abstract, countable/uncountable.
Test: can you put the or a before it? Can you make it plural? If yes to either → it's functioning as a noun.
C2 | Proficiency
- ✅ His was a pyrrhic victory, if ever there was one. — literary allusion + inversion
- ✅ She'd have been none the wiser had he not let slip. — inverted conditional + idiom
- ✅ The proposal, laudable though it may be, fails on pragmatic grounds. — formal concession
- ✅ "Nice weather," he deadpanned, eyeing the hailstones. — irony + narrative register
These are C2 patterns — the highest CEFR level. At C2 you handle literary allusion, irony, any register, and complex written argument with native-like precision across all subjects.
Marker: if your English is indistinguishable from an educated native speaker's across registers, you're C2.
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.