When do you use relative pronouns?
Each relative pronoun has a specific function and usage in a sentence. Therefore, choosing the appropriate relative pronoun for a relative clause will depend on what the sentence is referring to. For example:
Who: refers to people, or sometimes animals.
Theseus, who was strong and brave, defeated the monstrous minotaur.
Theseus plunged his sword into the belly of the minotaur who fell to the ground with an almighty crash.
Albert Einstein was a famous physicist who developed the theory of relativity.
Whom: refers to people in more formal styles of writing.
The landlady of 221B Baker Street, whom Sherlock adored, was not a talented chef.
They were old friends, whom were easy company.
Whose: demonstrates possession by people, animals and sometimes places or things.
Abigail, whose party it was, offered everybody a slice of cake.
It was Bess, whose bedroom window faced the courtyard of the inn.
Which: refers to animals, places or things.
The old man reached for the tea pot on the top shelf, which wasn't easy with a bad back.
The cat, which had been snoozing in the sun all afternoon, was curled up on the windowsill.
That: refers to people, animals, places or things (instead of who, whom or which) and offers a slightly more informal tone.
The train, that had arrived later than expected, was packed with commuters.
This is the wall that Hadrian built in 122 CE.
When: refers to a time or time period.
Not a day goes by when I don't regret my decision.
Encourage children to experiment with the relative pronoun used to introduce a given relative clause, so they can see the impact that pronoun choice has on the meaning and precision of the resulting sentences. This will help children to identify and use appropriate relative pronouns in their own writing.