Reduced relative clauses: people waiting, a letter sent yesterday

A shorter clause after a noun

A relative clause gives information about a noun. The full clauses below have a relative pronoun such as who, which or that and a verb with tense. A reduced relative clause can use a participle instead. A participle is a verb form such as waiting, repaired or written.

Keep the shorter clause next to the noun it describes. In the first example, waiting describes the visitors. In the second, delivered describes the parcel. The whole sentence still needs its main verb: have or is.

Active meaning with -ing

Use an -ing participle when the noun does the action. You can remove who, which or that and a form of be from a continuous relative clause.

• The woman who is checking the tickets is our guide. / The woman checking the tickets is our guide.

An -ing clause can also describe a general activity. It does not always mean that something is happening right now.

• Courses that include a laboratory session cost more. / Courses including a laboratory session cost more.

The -ing form does not show tense by itself. Use the sentence and context to understand the time.

• I spoke to the man carrying the ladder. In that past situation, he was carrying the ladder.

Passive meaning: noun + past participle

Use a past participle when the noun receives the action. The past participle ends in -ed for regular verbs, such as repaired. Irregular forms include written, made and sent. It is not simply a past-tense ending.

• The chairs that were repaired last week are back. / The chairs repaired last week are back.
• We found a note written in green ink. Someone wrote the note. The note did not write anything.

A past participle does not give a precise time by itself. In the first example, last week supplies the time. Keep time expressions when your reader needs them.

An action in progress: being + past participle

To keep a continuous passive meaning, use being + past participle. The noun receives an action that is in progress in the situation.

• The road which is being widened will reopen in June. / The road being widened will reopen in June.

Compare the road widened last year with the road being widened now. The first describes the result of earlier work; the second describes work in progress. Do not drop being if that would change the meaning you need.

Check the subject, not just the next word

For the active and passive participle patterns above, the noun before the clause corresponds to its subject. With a passive verb, that subject receives the action.

In the last row, we is the subject of hired. The engineer is its object. Leaving out who is possible, but that is object-pronoun omission, not a change to an -ing clause. The engineer hiring would mean that the engineer does the hiring. See Leaving out the relative pronoun: the people we met.

These noun descriptions are different from an introductory participle clause such as Walking home, I saw a fox. Here the description follows its own noun. It does not have to describe the main-clause subject: I thanked the engineer inspecting the lift.

Do not change every verb mechanically

A shorter clause must preserve the meaning, not just save words. Keep a full relative clause when its tense or other wording makes an important distinction.

• The passenger who lost her passport yesterday called the airline.

This identifies her through a completed event. The passenger losing her passport suggests an event in progress, so it is not the same description. Keep who lost for the intended meaning.

Do not use having + past participle as an automatic replacement for a perfect relative clause. Perfect participles are generally not used in this noun-description pattern. They have other uses in Past and perfect participle clauses: invited, having checked.

Descriptions with be, and extra information

Some full clauses with be can become a shorter description without a participle. Remove both the relative pronoun and be when the remaining words work as a description after the noun.

• The keys that are beside the sink are mine. / The keys beside the sink are mine.

You can also put a noun phrase after a name to add extra information. A noun phrase is a noun with words that belong to it. Keep commas around the extra information when the main sentence continues.

• We thanked Laila, who is our local guide, after the tour. / We thanked Laila, our local guide, after the tour.

A participle clause can add extra information too. Use commas for that meaning, as you would with a full non-defining relative clause.

• The old station, restored in 2018, now has a café. The restoration is extra information about the station.

To-infinitives after first, last and only

After expressions such as the first, the last or the only followed by a noun, a to-infinitive can describe the person or thing. This is another non-finite pattern, not an -ing form.

• Marta was the first volunteer to arrive. She was the first volunteer who arrived.
• Leo was the only applicant to bring a portfolio.

You can use to have + past participle to mark an earlier completed action.

• She was the first runner to have completed all four stages. She was the first runner who had completed all four stages.

Where these patterns fit

These shorter descriptions can make writing more concise. They are useful in academic writing, but a full relative clause is still an option. Choose the version that keeps your meaning clear. Do not remove a useful tense distinction merely to make a sentence shorter.

What comes next

See Defining relative clauses: who, which, that and Non-defining relative clauses: extra information with commas for full clauses and commas, Leaving out the relative pronoun: the people we met for leaving out an object pronoun, and Past and perfect participle clauses: invited, having checked for other participle-clause patterns.