Relative clauses – Part Two: Omissions

When creating a sentence using a defining relative clause, it is useful to understand that it is common in English to remove a relative pronoun when it describes the object of a sentence. 

When the sentence is in the passive voice, the auxiliary verbs be and have are usually removed as well.

For example, in the sentence below, the relative clause defines the object (the amount of food) and is in the passive voice (is eaten) so the relative pronoun (that) and the auxiliary verb be (is) can be removed.

The line graph shows the amount of food that is eaten by an average Chinese household in one week.

The line graph shows the amount of food eaten by an average Chinese household in one week.

It is not an error to keep the relative pronoun and the auxiliary verb in these sentences, but the essay will read more naturally if this rule is learnt and used effectively by test-takers. 

Remember: 

When the relative clause refers to the object of the main verb it can be removed (together with auxiliary verbs in the passive voice).

When the relative clause refers to the subject of the verb it cannot be removed.

Examples of IELTS Task One sentences with relative clauses defining the subject:

The number of companies that sold cars rose sharply.

The diagrams show the number of students who applied for university.

The profits for the two largest power stations that sold electricity in the UK in 2020 were significantly higher.

The diagrams show the sales figures for each factory that relocated to the EU in 2018..

The diagrams illustrate information about the number of homes that spent more than 500 dollars per month on electricity in three countries. 

Ask yourself who did the action. When the doer is directly before the relative clause it defines the subject. In these sentences nothing should be removed.

Examples of IELTS Task One sentences with relative clauses defining the object (before and after omissions)

When the object of an action is before the relative clause (i.e the thing that the action was done to) the relative clause and auxiliary can be removed. This is often when the action is in the passive voice.

The number of cars that were sold rose significantly.

The number of cars sold rose significantly.

The diagrams show the number of houses that have been sold since June.

The diagrams show the number of houses sold since June.

The diagrams show the number of applications that were made by students.

The diagrams show the number of applications made by students.

The amount of electricity that was sold in the UK during 2020 was significantly higher.

The amount of electricity sold in the UK during 2020 was significantly higher.

The diagrams show the number of guitar sales that were recorded in June.

The diagrams show the number of guitar sales recorded in June.

The diagram illustrates the number of international students who were expelled from universities in 2015.

The diagram illustrates the number of international students expelled from universities in 2015.

The diagrams illustrate information about the amount of electricity that homeowners used from 2007 to 2016.

The diagrams illustrate information about the amount of electricity homeowners used from 2007 to 2016.

Future tenses

Caution – For future tenses do not omit relative pronouns when using will in the passive voice

Active

The diagrams illustrate information about the amount of electricity that homeowners will use from 2007 to 2016. ✔︎

The diagrams illustrate information about the amount of electricity homeowners will use from 2007 to 2016. ✔︎

Passive

The diagrams show predictions about the number of houses that will be sold until June 2030. ✔︎

The diagrams show predictions about the number of houses sold until June 2030. ✘

The diagrams show predictions about the number of houses will be sold until June 2030. ✘