Advanced relative clauses. 45 questions on reduced relative clauses, preposition + relative pronoun, sentential relative clauses, and formal register.
What this test covers
- Reduced Relative Clauses
- Preposition + Relative Pronoun
- Sentential Relatives & Formal Usage
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All 45 questions with answers
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Q1Select the most appropriate reduced form of the sentence: 'The software, which was developed by the team, is now ready.'
Answer: D. The software, developed by the team, is now ready.
This is a reduction of a non-restrictive relative clause (a clause providing extra info, marked by commas) in the passive voice. By removing the relative pronoun 'which' and the auxiliary 'was', the clause becomes a past participle phrase. 'Developed' functions as an adjectival modifier of 'The software'. 'Developing' is incorrect because it implies an active meaning (the software is doing the developing), whereas the software is the recipient of the action. The option starting with 'that was developed' is incorrect because 'that' cannot be used in non-restrictive clauses.
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Q2Rewrite the following sentence for formal register: 'The terms that the agreement was signed under are binding.'
Answer: B. The terms under which the agreement was signed are binding.
Formal register typically avoids 'preposition stranding'—leaving the preposition at the end of the clause. Instead, the preposition is moved to a position before the relative pronoun (a process called pied-piping). In such cases, 'which' is the required pronoun for objects, resulting in 'under which'. 'That' cannot follow a preposition directly. 'To which' is incorrect because the standard idiomatic expression is to be 'under' terms or conditions, not 'to' them.
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Q3Select the most appropriate reduced form of the sentence: 'The committee members, who are attending the summit, will arrive at noon.'
Answer: A. The committee members, attending the summit, will arrive at noon.
Active relative clauses are reduced by removing the relative pronoun and the auxiliary verb 'be', leaving a present participle phrase (-ing form). Here, 'attending the summit' functions as an adjectival phrase modifying 'committee members'. 'Which' is incorrect because it cannot refer to human antecedents. 'That' is incorrect here because it is restricted to defining clauses, and this sentence uses commas, indicating a non-restrictive (non-essential) clause.
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Q4Complete the sentence: 'Everything ___ you said during the meeting has been recorded in the minutes.'
Answer: D. that
When the antecedent is an indefinite pronoun such as 'everything', 'nothing', or 'all', the relative pronoun 'that' is preferred over 'which' in restrictive clauses. 'What' is a nominal relative pronoun that functions as its own antecedent (meaning 'the thing that'); using it here would be redundant because the noun 'Everything' is already present. 'Who' and 'where' are semantically incorrect as they refer to people and places respectively.
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Q5Choose the correct sentential relative clause: 'The merger failed, ___ worried investors significantly.'
Answer: B. which
A sentential relative clause refers back to the entire idea of the preceding clause rather than a single noun. 'Which' is the only relative pronoun that can fulfill this function in English. 'That' is prohibited in non-restrictive or sentential clauses. 'What' is a nominal relative pronoun that cannot follow an antecedent clause. 'Where' is used only for locations and does not fit the logic of the sentence.
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Q6Rewrite the following sentence for formal register: 'The candidate that we spoke to yesterday showed great promise.'
Answer: C. The candidate to whom we spoke yesterday showed great promise.
In formal English, when a verb requires a preposition (speak to), that preposition is placed before the relative pronoun. When referring to a person as the object of a preposition, the objective form 'whom' is mandatory. Using 'who' or 'that' with a 'stranded' preposition at the end is common in speech, but 'to whom' represents the highest formal register. The other options are grammatically incomplete because they omit the required preposition 'to' entirely.
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Q7Select the most appropriate reduced form of the sentence: 'The report, which was finished last week, is on your desk.'
Answer: C. The report, finished last week, is on your desk.
The passive non-restrictive clause 'which was finished' is reduced to a past participle phrase by removing the relative pronoun and the verb 'be'. 'Finished last week' acts as a concise adjectival modifier. 'Finishing' is incorrect because it has an active meaning, suggesting the report was performing the action of finishing something else. Using 'that' is incorrect because 'that' cannot be used in non-restrictive clauses (clauses set off by commas).
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Q8Rewrite the following sentence for formal register: 'The conditions that the experiment was conducted under were stable.'
Answer: A. The conditions under which the experiment was conducted were stable.
Formal academic prose prefers moving the preposition to the front of the relative clause rather than leaving it at the end. 'Under which' is the correct formal construction because we conduct experiments 'under' conditions. 'That' cannot be preceded by a preposition. 'On which' is idiomatically incorrect in this context; while we might use 'on' for terms or bases, 'under' is the standard collocation for 'conditions'.
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Q9Complete the sentence: 'The only thing ___ matters now is the project deadline.'
Answer: B. that
The relative pronoun 'that' is preferred when the noun being modified (the antecedent) is preceded by 'the only', 'the first', 'the last', or a superlative. 'Who' and 'whom' are used only for human referents. 'What' is a nominal relative pronoun meaning 'the thing that', so using it after 'The only thing' would result in a double antecedent error ('The only thing the thing that matters').
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Q10Select the most appropriate reduced form of the sentence: 'The employees who are working on the project are exhausted.'
Answer: B. The employees working on the project are exhausted.
This restrictive relative clause can be reduced to a present participle phrase by removing the relative pronoun 'who' and the auxiliary 'are'. The resulting phrase 'working on the project' serves as a post-nominal modifier (a modifier following a noun). This reduction is only possible when the relative pronoun is the subject of the original clause. Using 'which' is incorrect because 'which' cannot refer to people ('employees').
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Q11Choose the correct sentential relative clause: 'The CEO resigned unexpectedly, ___ surprised the entire board.'
Answer: C. which
The pronoun 'which' acts as a sentential relative, where its antecedent is the entire previous statement ('The CEO resigned unexpectedly'). 'That' cannot be used in this capacity. 'Who' would refer back to the CEO as a person, but it was the fact of the resignation that surprised the board, not the person himself. 'What' cannot be used to refer back to a preceding clause in this way.
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Q12Complete the sentence: 'The equipment ___ was purchased last year is state-of-the-art.'
Answer: B. that
In restrictive relative clauses (those essential to the sentence meaning) modifying inanimate objects, 'that' or 'which' is required. 'Who' and 'whom' are strictly for human referents. 'What' is a nominal relative pronoun—it functions as both the noun and the pronoun. Since the noun 'equipment' is already present, 'what' is grammatically redundant.
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Q13Select the most appropriate reduced form of the sentence: 'The documents, which were signed by the CEO, are confidential.'
Answer: A. The documents, signed by the CEO, are confidential.
To reduce a passive relative clause, the relative pronoun and the auxiliary verb 'be' are omitted, leaving a past participle phrase. 'Signed by the CEO' correctly modifies 'the documents'. 'Signing' is incorrect because it describes an active process, implying the documents were doing the signing. Using 'that' is incorrect because 'that' cannot be used in non-restrictive clauses.
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Q14Rewrite the following sentence for formal register: 'The criteria that candidates are assessed by are quite strict.'
Answer: D. The criteria by which candidates are assessed are quite strict.
Formal register requires 'pied-piping'—placing the preposition 'by' before the relative pronoun 'which'. Since the standard phrase is to 'assess by criteria', 'by which' is the correct construction. 'In which' is semantically inappropriate. Using 'that' or leaving 'by' at the end of the clause is acceptable in standard English but is considered less formal in academic or legal contexts.
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Q15Select the most appropriate reduced form of the sentence: 'The students who are sitting in the library are preparing for finals.'
Answer: C. The students sitting in the library are preparing for finals.
A restrictive relative clause containing a progressive verb (be + -ing) is reduced by removing the subject pronoun 'who' and the auxiliary 'are'. This leaves the present participle 'sitting', creating a concise noun-modifier relationship. Using 'which' is incorrect because 'which' cannot refer to people. The option with 'that' is grammatically correct but is not a 'reduced' form.
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Q16Choose the correct sentential relative clause: 'He failed his exams, ___ was a disappointment to his parents.'
Answer: B. which
'Which' is used here as a sentential relative to modify the entire preceding fact (the fact that he failed). 'That' is never used in this type of non-restrictive clause. 'What' is a nominal relative pronoun (meaning 'the thing that') and cannot take a preceding clause as an antecedent. 'Where' refers to location and is irrelevant here.
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Q17Rewrite the following sentence for formal register: 'The policy which we adhere to is published online.'
Answer: B. The policy to which we adhere is published online.
In formal registers, the preposition 'to' (which is required by the verb 'adhere') is moved to the front of the clause, before 'which'. 'Preposition stranding' (leaving 'to' at the end) is avoided in formal writing. 'Where' is a relative adverb for locations and does not fit. 'That' cannot be used after a preposition.
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Q18Select the most appropriate reduced form of the sentence: 'The man who is standing at the reception is waiting for you.'
Answer: A. The man standing at the reception is waiting for you.
The restrictive relative clause 'who is standing' is reduced by removing the relative pronoun 'who' and the auxiliary 'is'. This leaves the present participle phrase 'standing at the reception', which acts as an adjective modifying 'The man'. Using 'which' is incorrect because 'which' cannot refer to a human subject like 'the man'.
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Q19Complete the sentence: '___ surprised everyone was the speed of their delivery.'
Answer: A. What
This sentence requires a nominal relative pronoun (a pronoun that acts as its own noun/antecedent) to serve as the subject of 'was'. 'What' is the standard choice, meaning 'the thing that'. 'Which' and 'that' are relative pronouns that require an explicit noun before them to refer back to. 'The thing' is incorrect because it would require a following relative pronoun (e.g., 'The thing that surprised...').
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Q20Select the most appropriate reduced form of the sentence: 'The data which were collected by the researchers are now being analyzed.'
Answer: C. The data collected by the researchers are now being analyzed.
The passive restrictive relative clause 'which were collected' is reduced to the past participle 'collected' by omitting the pronoun and the verb 'be'. 'Collecting' would be an active participle, which would incorrectly imply that the data performed the action of collecting. Note that 'data' is treated as a plural noun here, hence the use of 'were'.
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Q21Rewrite the following sentence for formal register: 'The professor who I spoke to is an expert in linguistics.'
Answer: A. The professor to whom I spoke is an expert in linguistics.
In formal registers, when a person is the object of a preposition (to speak to someone), the preposition is moved to the front and followed by the objective case pronoun 'whom'. Using 'who' or 'that' with a stranded preposition is standard for neutral conversation but lacks the technical precision required for formal academic or professional contexts.
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Q22Select the most appropriate reduced form of the sentence: 'The report, which was submitted yesterday, is invalid.'
Answer: A. The report, submitted yesterday, is invalid.
A non-restrictive passive relative clause (one providing extra info using commas) is reduced by removing the relative pronoun and the auxiliary 'was'. This leaves a past participle phrase ('submitted yesterday'). 'Submitting' is an active participle and would imply the report performed the action of submitting, which is logically impossible.
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Q23Complete the sentence: 'Nothing ___ happened during the night was unusual.'
Answer: C. that
Restrictive relative clauses following indefinite pronouns like 'nothing', 'everything', or 'anything' typically use 'that' as the relative pronoun. 'What' is a nominal relative pronoun and cannot follow an antecedent like 'nothing'. 'Who' and 'where' are used for people and places, respectively, and do not match 'nothing'.
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Q24Rewrite the following sentence for formal register: 'The client that we are dealing with is very difficult.'
Answer: A. The client with whom we are dealing is very difficult.
To achieve a formal register, the preposition 'with' must be moved from the end of the clause to the position before the relative pronoun. Because 'client' is a person and is the object of the preposition, 'whom' is the required pronoun. 'Which' is used for objects, not people. 'That' cannot follow a preposition directly.
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Q25Complete the sentence: 'The damage ___ resulted from the storm is extensive.'
Answer: D. that
'That' is the standard relative pronoun for a restrictive clause with an inanimate antecedent ('damage'). 'Who' and 'whom' are reserved for humans. 'What' is a nominal relative pronoun (meaning 'the thing that') and cannot follow a noun like 'damage' as it would create a redundant antecedent.
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Q26Select the most appropriate reduced form of the sentence: 'The woman who is waiting outside is the manager.'
Answer: A. The woman waiting outside is the manager.
Reducing the restrictive relative clause 'who is waiting' involves removing the relative pronoun and the verb 'be', resulting in the present participle phrase 'waiting outside'. This functions as a more concise modifier. Using 'which' is incorrect because 'which' refers to objects, not people.
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Q27Rewrite the following sentence for formal register: 'The extent that the reforms have succeeded is unclear.'
Answer: A. The extent to which the reforms have succeeded is unclear.
'The extent to which' is a fixed formal construction. The noun 'extent' collocations with the preposition 'to' (e.g., 'to a great extent'). In formal writing, this preposition is fronted before 'which'. 'In which' is incorrect because it does not match the idiomatic prepositional requirement of 'extent'.
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Q28Rewrite the following sentence for formal register: 'The mechanism which the virus operates through remains a mystery.'
Answer: D. The mechanism through which the virus operates remains a mystery.
Formal style avoids preposition stranding by placing 'through' before 'which'. The verb 'operate' here relates to the 'mechanism' via the preposition 'through' (to operate through a mechanism). 'On which' is less precise because 'through' specifically describes the process or pathway the virus uses.
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Q29Select the most appropriate reduced form of the sentence: 'The policy, which was adopted in 2020, is changing.'
Answer: A. The policy, adopted in 2020, is changing.
Passive non-restrictive relative clauses are reduced to a past participle phrase by omitting 'which was'. 'Adopted in 2020' acts as a non-essential adjectival phrase. 'Adopting' is active and would imply the policy itself performed the action of adopting something else. 'That' is never used in non-restrictive (comma-separated) clauses.
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Q30Complete the sentence: 'Someone ___ can help you with this is available in the office.'
Answer: D. who
The relative pronoun 'who' is used for human subjects (someone). 'Who' is used here as the subject of the verb 'can help'. 'Whom' is the objective case, 'which' is for inanimate objects, and 'what' is a nominal relative pronoun that cannot follow a specific noun like 'someone'.
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Q31Complete the sentence: 'What the police failed to find ___ sufficient evidence.'
Answer: A. was
The nominal relative clause 'What the police failed to find' acts as the subject of the sentence. In such 'pseudo-cleft' constructions, the verb usually agrees with the following complement. Since 'evidence' is an uncountable (singular) noun, 'was' is required. 'That was' and 'which was' would make the sentence ungrammatical by adding unnecessary relative pronouns.
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Q32Select the most appropriate reduced form of the sentence: 'The students who are preparing for the exam are very stressed.'
Answer: C. The students preparing for the exam are very stressed.
The restrictive relative clause 'who are preparing' can be reduced to the present participle 'preparing'. This reduction (dropping the pronoun + 'be') is standard in active voice clauses to streamline the sentence. Using 'which' is incorrect because 'which' cannot refer to people. The option with 'that' is not a 'reduced' form.
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Q33Select the most appropriate reduced form of the sentence: 'The book which is lying on the table is mine.'
Answer: A. The book lying on the table is mine.
The restrictive relative clause 'which is lying' is reduced to the present participle 'lying'. This is valid when the relative pronoun is the subject and the verb is in a progressive form. Using 'who' is incorrect because 'who' is only for people. The option with 'which is lying' is correct but is not a 'reduced' form.
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Q34Complete the sentence: 'The artist ___ paintings are on display is famous.'
Answer: B. whose
The relative pronoun 'whose' is the possessive form used to show that the paintings belong to the artist. 'Whose' is the only possessive relative pronoun in English and can be used for both people and objects. 'That' and 'which' cannot indicate possession, and 'he' is a personal pronoun that would make the clause ungrammatical.
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Q35Rewrite the following sentence for formal register: 'The circumstances which the delay occurred under are being investigated.'
Answer: D. The circumstances under which the delay occurred are being investigated.
In formal writing, prepositions associated with nouns (like 'under' for 'circumstances') are fronted before the relative pronoun 'which'. 'Under which' is the standard formal construction. 'On which' is idiomatically incorrect because events occur 'under' circumstances, not 'on' them.
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Q36Select the most appropriate reduced form of the sentence: 'The letter, which was sent last week, arrived.'
Answer: C. The letter, sent last week, arrived.
The non-restrictive passive relative clause 'which was sent' is reduced to the past participle 'sent'. This concisely adds non-essential information. 'Sending' would be an active participle, implying the letter performed the action. Using 'that' is incorrect because 'that' cannot be used in non-restrictive clauses.
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Q37Select the most appropriate reduced form of the sentence: 'The delegates who are attending the summit are in the lobby.'
Answer: C. The delegates attending the summit are in the lobby.
This reduction transforms the restrictive relative clause 'who are attending' into the present participle phrase 'attending the summit' by removing the subject pronoun 'who' and the auxiliary 'are'. Using 'which' is incorrect because 'which' cannot refer to people. The option with 'that' is a standard relative clause but not a 'reduced' form.
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Q38Complete the sentence: 'Everything ___ you need is in the box.'
Answer: B. that
'That' is the preferred relative pronoun in restrictive clauses following the indefinite pronoun 'everything'. 'What' is a nominal relative pronoun that functions as both noun and pronoun; since the noun 'everything' is already the antecedent, using 'what' would be redundant. 'Who' and 'whom' are for humans only.
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Q39Rewrite the following sentence for formal register: 'The means which it was approved by is now public.'
Answer: A. The means by which it was approved is now public.
In formal register, the preposition 'by' (required for 'approved by a means') is placed before the relative pronoun 'which'. This avoids 'preposition stranding'. 'Means' correctly takes 'by' to denote the method of approval. 'In which' is incorrect because it does not match the standard prepositional phrase 'by means of'.
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Q40Select the most appropriate reduced form of the sentence: 'The flowers, which were planted in spring, are blooming.'
Answer: A. The flowers, planted in spring, are blooming.
The passive non-restrictive clause 'which were planted' is reduced to the past participle phrase 'planted in spring' by omitting the relative pronoun and the verb 'were'. 'Plant' is a base form and cannot function as a modifier here. Using 'that' is incorrect because 'that' is not used in non-restrictive clauses.
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Q41Rewrite the following sentence for formal register: 'The conditions that the sample was stored under were ideal.'
Answer: B. The conditions under which the sample was stored were ideal.
Formal English requires fronting the preposition 'under' so that it precedes 'which'. 'Under which' is the idiomatic prepositional phrase for 'conditions'. Leaving the preposition at the end ('under') is acceptable in speech but avoided in formal academic and professional registers. 'On which' is incorrect for the noun 'conditions'.
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Q42Choose the correct sentential relative clause: 'The team won the game, ___ surprised the fans.'
Answer: C. which
A sentential relative clause refers back to a whole preceding event. 'Which' is the only relative pronoun that can perform this function. 'That' cannot be used in non-restrictive or sentential relative clauses. 'Who' would refer back to the team (a group of people), but the surprise was caused by the victory, not the people themselves.
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Q43Complete the sentence: 'Anyone ___ can solve this is a genius.'
Answer: D. who
'Who' is the correct relative pronoun for a human subject ('Anyone'). 'Whom' is the objective case (used for objects of verbs or prepositions), but here we need a subject for 'can solve'. 'Which' is for objects/inanimates, and 'what' is a nominal relative that cannot follow an antecedent like 'anyone'.
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Q44Select the most appropriate reduced form of the sentence: 'The man who is sitting there is my uncle.'
Answer: B. The man sitting there is my uncle.
Reducing the restrictive relative clause 'who is sitting' to the present participle 'sitting' creates a more concise noun phrase. This transformation is possible when the relative pronoun is the subject and the verb is in a progressive aspect. Using 'which' is incorrect because 'which' is used for objects/animals, not people.
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Q45Complete the sentence: 'What the report failed to address ___ the core issue.'
Answer: C. was
The nominal relative clause 'What the report failed to address' functions as the subject of the sentence. In such pseudo-cleft structures, the verb 'be' should agree with the following singular complement ('the core issue'), necessitating the singular form 'was'. 'Been' and 'being' are non-finite forms that cannot serve as the main verb of the sentence.
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