Contrasting non-defining relative clauses like “My sister, who lives with me, has seven cats” with defining relative clauses like “My sister who lives with me has seven cats” is both useful and difficult to avoid when teaching relative clauses. However, it also opens up a whole can of worms of complications and potential student questions. Especially at lower and intermediate levels, you may therefore want to start with a lesson on just non-defining relative clauses like “My geography teacher, who might have also taught you when you were there, suggested studying anthropology instead”. This article gives ideas for how to present and practise only non-defining relative clauses for a lesson or two, with just a little on contrasting them with other forms in case there are student questions. There are also articles on this site on teaching defining relative clauses and both defining and non-defining relative clauses together.
What students need to know about non-defining relative clauses
As the name suggests, “non-defining relative clauses” don’t tell us the vital information of who or what we are talking about (as defining relative clauses like “My sister who you met yesterday is now banned from this house” would). Instead, it adds extra information which is nice but we could live without, as in “This couch, which my sister bought for me, has fleas”. The fact that it is just extra information is represented by commas in writing and by a pause and change in tone while speaking. This makes it almost the same as the brackets in “This couch (which my sister bought for me) has fleas”. This meaning can be reinforced with words like “incidentally” (“Thanks for the blanket, which incidentally needs a good wash”) and “by the way”.
The most common relative pronouns in non-defining relative clauses are:
- which (“This table goes with these two chairs, which look completely different but are actually a set”, “This bed here, in which I was born, needs to go to the dump”)
- who (“My ex-boss, who might be my boss again quite soon by the way, had exactly the same bag”)
- when (“Last summer, when we first met, might well have changed my life forever”)
- where (“The most famous Northern town for people who wear little even on winter nights is Newcastle, where I went to university”)
Famously, “that” is the most common and useful relative pronoun in defining relative clauses, but is never correct in non-defining relative clauses like “My favourite ice cream is this flavour, that I only discovered last year” X.
Similarly, relative pronouns can never be taken out of non-defining relative clauses (unlike in defining relative clauses like “The man I punched yesterday punched me today”). Reduced relative clauses like “The man, brushing his teeth, looked at me angrily” are possible, but these are exactly the same as with defining relative clauses and so it doesn’t make sense to deal with reduced relative clauses in a lesson on just non-defining relative clauses.
The fact that you can’t use “that” in non-defining relative clauses can make it difficult to avoid the relative pronoun “whom”, despite it being rare in modern English. However, it is always possible to rephrase or update the sentence to avoid it in some way, so I very rarely teach it.
Common student problems with non-defining relative clauses
Perhaps the most common error with non-defining relative clauses is using “that”. I have sometimes perhaps made this worse in my own classes by really recommending “that” as an easy replacement for both “which” and “who” when we covered defining relative clauses. You may therefore want to de-emphasise “that” when covering defining relative clauses, particularly as some people disapprove of “that” for “who”.
Some teaching materials can overemphasise the use of non-defining relative clauses in the middle of sentences, making students confused when they then come across sentences like “This is my sister and this is my older brother, who lived just down the road from here when he was at university”. This can be solved by making sure there is a good mix of examples of relative clauses in different positions in the presentation and practice stages.
Most other common errors are to do with mixing up the meaning, punctuation and/ or pronunciation of defining and non-defining relative clauses, so are dealt with in the article on both forms.
How to present non-defining relative clauses
Initial tasks which would give students exposure to non-defining relative clauses that they can then analyse include:
- matching subjects, non-defining relative clauses and the rest of the sentence by their general knowledge (“Napoleon + , who wasn’t as short as people think, + was born in Corsica + , which had only been part of France for one year at that time”)
- matching subjects, non-defining relative clauses and the rest of the sentence by what they can guess about the teacher (“Tunbridge Wells + , which is a nice but amazingly boring place, + is where I grew up”)
- working out which non-defining relative clauses contain false information
- working out which non-defining relative clauses in different sentences need to be swapped
- taking out the non-defining relative clauses which are least interesting and/ or most off topic
- adding the non-defining relative clauses to the right places in a text (maybe with the commas left in the text to show the possible places if you want to make the task really easy)
- doing a listening or reading comprehension task for which at least some answers are related to non-defining relative clauses in the text
- deciding which descriptions with non-defining relative clauses make the things which are being described sound most attractive
After completing that comprehension task, students can try to work out which is the optional extra info in each sentence, how commas are used, which relative pronouns are used and when, and how they should pronounce non-defining relative clauses.
A possible start which gets straight to the grammar is for students to read a text with commas missing as their teacher reads it out. As they listen and read, they try to put commas in the right places from their teacher’s pronunciation, the meaning of the text, their grammar knowledge, etc.
A similar but more complex task that could work for this language point is a grammar dictation/ dictogloss. With their pens down, students listen to the teacher read out a short text with a range of different non-defining relative clauses. Still with their pens down, they then hear it again. After that, they write down all that they can remember, put their ideas together with a partner, listen a third and final time with their pens down, polish it up as much as they can, then see the original text.
How to practise non-defining relative clauses
Some of the presentation tasks above could also be done as a practice stage, perhaps with students making up similar tasks with general knowledge, personal information, false information, etc to test each other with, for example:
- students make up true sentences with non-defining relative clauses then split them into different bits for other students to put back together
- students make up a mix of true and false sentences with non-defining relative clauses
- students make sentences in which either the main clause or the non-defining relative clause are false (but not both, as in “Brighton and Hove Albion, which is in the English Premiership, has the nickname ‘the Puffins’”)
- writing what they think are good sentences with non-defining relative clauses, then trying to improve those of another group
Infinite non-defining relative clauses practice
Students choose or make a simple sentence like “The Aya Sofia is in Istanbul” and take turns making the sentence longer by adding extra information, including in non-defining relative clauses. For example, the chain could be, step by step:
- The Aya Sofia, which is a mosque again, is in Istanbul.
- The Aya Sofia, which is a mosque again, is in Istanbul, which is the biggest city but not the capital of Turkey.
- The Aya Sofia, which is a mosque again, is in Istanbul, which is the biggest city but not the capital of Turkey, where other famous mosques include the Blue Mosque.
This can be done with factual information about real things, about real things but also allowing them to use their imaginations, or with completely made-up places, monsters, etc.
This is even more confusing but amusing if you allow the bad habit of non-defining relative clauses within non-defining relative clauses (“The Aya Sofia, which is a mosque, where Muslims worship, is in Istanbul”, etc)
Non-defining relative clauses boasting game
Students choose two similar things to each other, e.g. one chooses an elephant and the other chooses a giraffe. They then try to make descriptions that make their choice sound better than their partner’s, taking turns to add to or change the description to make it better and better. This should naturally lead to non-defining relative clauses without needing to force it, particularly if you limit them to one sentence each.
Non-defining relative clauses text building
Give students a text with all the non-defining relative clauses taken out for them to make more interesting by adding extra information to. They then compare with another group, giving feedback on which things are too off topic, etc.
Non-defining relative clauses storytelling task
One student says or writes a line to continue a story like “The prince rode his horse through the haunted woods”. The next person adds a non-defining relative clause to that sentence (“The prince, who could feel that something bad was going to happen, rode his horse through the haunted woods”). They then make a simple sentence to continue the same story for their partner to add a non-defining relative clause to. They continue in the same way until the story comes to a natural end or the teacher tells them to try to bring it to an end within a certain time or certain number of extra sentences.