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Grammartier

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Interactive Grammar: Advanced Relative Clause Reduction

Reduce and simplify relative clauses in formal contexts using participles and infinitives.

Grammar Explanation · Authentic Examples · Practice Exercises

Lesson progressNot started
Duration
~51 min
Exercises
34
Level
Advanced

Overview

Reduce and simplify relative clauses in formal contexts using participles and infinitives.

Reducing to Participles

  • Activethe researcher who is investigating → the researcher investigating
  • Passivethe data that was collected → the data collected
  • Perfectcompanies that have merged → companies having merged
  • RuleOmit 'which/who + be' — standard in academic writing.

Reducing to Infinitives

  • Ordinal: the first candidate who met the criteria → the first to meet
  • Only: the only approach that works → the only approach to work
  • Superlative: the most efficient method to adopt
  • The infinitive reduction implies potential or recommended action.

When NOT to Reduce

  • Non-defining clauses: My colleague, who works in Rome, — cannot reduce (comma = no reduction).
  • When the relative pronoun is object: the report which she wrote — reduction is ambiguous.
  • When reduction creates ambiguity: the researcher studying — studying what?

When to use

Academic writing

Studies conducted over a decade revealed consistent patterns.

Business reports

The only candidate to fulfil all criteria was shortlisted.

Legal documents

The party bearing responsibility shall pay full compensation.

Journalism

The minister appointed last year has now resigned.

Relative Clause Reduction: Multiple Choice

Choose the correct reduced form for each formal sentence

Multiple Choice10 questions
1'The researcher who is conducting the study' reduced:
2'The data that was collected last year' reduced:
3'The first candidate who met all criteria' reduced:
4Non-defining clause — can it be reduced? 'My colleague, who lives in Paris, called.'
5'Companies that have merged recently' reduced:
6'The only approach that works in this context' reduced:
7'Reports that are produced quarterly' reduced:
8When should you NOT reduce a relative clause?
9'The best strategy that the board can adopt' reduced:
10'Staff who are based in the London office' reduced:

Reduce the Relative Clause

Replace the full relative clause with the reduced form

Fill in the Blanks8 questions
1The minister(who was appointed last year)has since resigned.
2The only proposal(that met the criteria)was submitted at the last moment.
3Studies(that were conducted overseas)revealed consistent patterns.
4The team(who is managing the project)submitted an interim report.
5Organisations(that have adopted the model)report improved efficiency.
6The best approach(that we could take)is to consult all stakeholders first.
7Participants(who were selected randomly)showed no significant performance differences.
8The framework(that was designed in 2018)has now been superseded.

Formal Reduction Practice

Rewrite each sentence by reducing the relative clause

Transform6 questions

1The report that was submitted by the audit team was praised. → (reduce passive RC)

2The first person who raised this concern was dismissed. → (reduce with infinitive)

3The party that bears responsibility must compensate the claimant. → (reduce active RC)

4The only argument that holds under scrutiny is the third. → (reduce with infinitive)

5Staff who are working remotely must log attendance daily. → (reduce active RC)

6Proposals that have been rejected previously may be resubmitted. → (reduce perfect RC)

Fix the Relative Clause Reduction Error

Identify and correct the incorrectly reduced relative clause

Error Fix10 questions

1The data collecting last month confirms the hypothesis.

2The researcher conducting the study in 2019 has since retired.

3The first analyst to reviewed the findings raised the alarm.

4Staff basing in the regional office attended the briefing.

5The only strategy working in that context was abandoned.

6Reports producing quarterly must follow the new format.

7Organisations having adopting the model report better outcomes.

8The proposal submitting last week was unanimously rejected.

9The best candidate meeting all criteria was offered the position.

10The framework designed to address the issue having been revised.

Frequently Asked Questions

What does this lesson on clauses cover?

Reduce and simplify relative clauses in formal contexts using participles and infinitives.

Which CEFR level is this lesson designed for?

This lesson is designed for Advanced (C1) learners and forms part of the Clauses section on Grammartier.

What is the best approach for studying this grammar topic?

Start with the definition, then study the examples carefully to understand how the pattern works in context. Practise identifying the structure in authentic sentences before producing your own — this recognition-first approach builds a strong foundation for accurate, confident use.

Your Grammar Learning Path

Follow the CEFR progression for this topic cluster.

  1. B2
    Participle Clauses
  2. B2
    Reduced Relative Clauses
  3. C1
    Advanced Relative Clause ReductionYou are here
  4. C1
    Complex Participle Clauses
  5. C2
    Complex Embedded Clauses

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