Conjunctions for non-defining relative clauses?


Are there defined and specific conjuctions for non-defining relative clauses? We usually have learned that conjunctions such as but, and, for, though, etc are related to non-defining relative clauses, so the reason there is "etc" is that we can relate all conjunctions for the grammar? Am I right? Thank you so much in advance. 


For example,


Tom is watching TV, while he is eating a snack.

-> Tom, who is eating a snack, is watching TV.

This is the last question about non-defining relative clauses for sure, so please help me out.

Do you think "while he" can be converted to , who like "and he, but she,etc" can be converted to ",who".

What do you think? I can't wait to hear from you.

edited Aug 29 '12 at 07:31 Hans Contributor

4 answers


I'm adding a second answer concerning your interest in non-defining relative clauses. I must admit I'm a bit befuddled about many of these questions. Perhaps there is a difference between how I was taught English grammar and how you are being taught.


I was taught that it is meaning, and meaning alone, in the context of the entire sentence that determines whether a clause is defining or non-defining. We use punctuation, not word choice, to convey the difference. Here is a quote from an old textbook of mine:


"A relative clause is an added part in a sentence that is used in relation to the main sentence. However, sometimes a relative clause is so important that the main sentence will be difficult to understand or have no meaning without it. This is called a defining relative clause. On the other hand, we often use a relative clause just to add extra information, which is usually indicated by the use of commas. The meaning of the main sentence will still be clear without it and it is therefore called a non-defining relative clause.  By using commas in written English and a slight pause in spoken English, two identically worded clauses can have different meanings when used in a sentence."


So no, there is not a defined list of conjunctions that can be used with non-defining relative clauses.

link edited Aug 29 '12 at 09:42 Jeff Pribyl Grammarly Fellow

Thank you for your time and effort and I would like to make my question simpler. Could you tell me yes or no to my questions?

Scree, which abounds in the Rocky Mountains, has its origins in the ice ages.
->Scree, abounding in the Rocky Mountains, has its origins in the ice ages.

Do you agree with ,which abounds-> abounding?
And what conjunction do you think was there in the original sentence?

The spectators, who roared approval, leaped to their feet.
>The spectators, roaring approval, leaped to their feet.

Do you agree with ,who roared->, roaring?
And what conjunction do you think was there in the original sentence?

Thank you and sorry for taking your time and effort a lot but I can feel that it is the most difficult moment for me to learn English.

HansAug 29 '12 at 10:22

The comment field is too limiting, so I have added another answer in response to your comments.

Jeff PribylAug 29 '12 at 16:02

add comment

Yes, your examples carry equivalent meaning.

But as a native English speaker, I have problems with the idea that there was an “original” sentence. Instead, I see two sentences with different sentence structures. I don’t “see” a missing or implied conjunction. One sentence pair  uses a gerund phrase as a subject complement. The subject complement acts as an adjective in your examples. The second pair contain relative pronoun clauses. Because you have set the relative clause off with commas, we see that these clauses are non-restrictive and can be omitted without altering the meaning of the main clause.

Try as I might, I cannot introduce a “missing” conjunction without creating an entirely different sentence structure. What I end up with is a sentence with a compound predicate. Compound predicates are two predicates, parallel in structure, and joined by a coordinating conjunction – and, but, or, yet, for, nor, so.

Scree abounds in the Rocky Mountains and originated in the Ice Age.

Unfortunately, the predicates in this sentence are not parallel – they do not agree in tense. We find that we cannot convert this example into this structure without changing your meaning. On the other hand, we can convert your second example into compound predicate form.

The spectators roared their approval and leapt to their feet.

I suspect the difference in how we view these sentence structures results from a basic difference between our native tongues. Research has shown that language colors how we think. You may be seeing something – due to the influence of your native tongue – that native English speakers do not see.

I hope this helps.  

link answered Aug 29 '12 at 16:01 Jeff Pribyl Grammarly Fellow

I really appreciate your help and time and effort and great answers!!

HansAug 30 '12 at 00:44

add comment

As edited, the punctuation leaves us slightly confused. It is not clear whether the commas are part of the question, or part of the sample text included in the question. I am assuming the question should read: Do you think ", while he" can be converted to ", who likes" -- and ", and he, but she, etc." can be converted to ", who"?


In answer to the first part -- can "while he" be converted to "who likes" -- is no, not without changing the meaning. For instance, watch what happens in the simple present tense: "Tom watches TV, while he eats a snack" means that both actions occur at the same time. But "Tom, who likes eating a snack, watches TV" just tells us that Tom likes eating a snack, but not when it is eaten. The watching and eating are separate events not linked in time.


On the other hand, when you use the helping verb "is" you can convert "while he is" to "who is".


In the second part of the question -- can "and he likes" be converted to "who likes". Yes, in most cases.


The lesson to be learned is that you can use different grammatical structures to convey the same meaning.

link comment answered Aug 29 '12 at 09:24 Jeff Pribyl Grammarly Fellow

Tom, who lives in the USA, is my friend. 

In this sentence, you are giving an extra information about Tom.


Tom is my friend and he lives in US.

You are using the conjunction "and" to join two independent clauses.

Tom is my friend.

He lives in US.

link answered Aug 29 '12 at 06:45 sanjay Expert

Thank you and sorry that I edited my original question to make what I would like to know clearer before I saw your answer.

HansAug 29 '12 at 07:24

add comment

Your answer

Write at least 20 characters

Have a question about English grammar, style or vocabulary use? Ask now to get help from Grammarly experts for FREE.