It is useful to define a sentence syntactically, as a unit which is one or more clauses.

1) The underlined words are an appositive phrase are they not?

2) What is the difference between this phrase and an elliptical clause? What I mean is, this phrase could have the words 'It is' preceding it (this example is not so good because 'as' would have to be omitted), and it would now be a clause, which is essentially what an elliptical clause is, I thought.

3) Are the underlined words in the sentence above, 'What I mean is', grammatically incorrect how I have placed a comma there? It seems to split the verb from the rest of the sentence. What are the underlined words. The first word is a fused relative pronoun, so maybe I just need to re-arrange the sentence.

Thanks in advance.
Eddie88 It is useful to define a sentence syntactically, as a unit which is one or more clauses.

1) The underlined words are an appositive phrase are they not?
I don't see how.

The infinitive phrase is a noun phrase serving as subject of the sentence, and is in good position to "accept" an appositive, but "as a unit" is adverbial, modifying only the infinitive, and not the infinitive phrase. Furthermore, the "which"-clause is essential, and can't be separated from "as a unit."

An appositive might be something like, "It is useful to define a sentence syntactically, a thankless task which is suitable for rascals and scalawags."

Best regards, - A.
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Hi Avangi,

I agree and understand with everything you say; this is a question I posted quite a while back, when I was first introduced to appositives. It is clearly not an appositive. As of late, I have been reading quite a lot about absolute phrases and the various uses of participles. I feel that grasping these two aspects of grammar would be useful to increase one's variety in writing.

And the appositive you used in apposition to 'useful' I found rather funny. I'm suprised you thought of a phrase to be in apposition with 'useful'; I know I couldn't this late.

I remember thinking a couple of times that your views on appositives were a bit skewed. I wanted to help, but hadn't thought about the subject for so long I was a little lost. I happened across that stray unanswered post and couldn't resist.

It's an interesting sentence. I think the basic form is "to define is useful." With the crazy inversion, I suppose you could say the appositive may be applied to either the subject or the predicate.

Well, on second thought, no, because useful is an adjective, and appositives (and their antecedents) must be nouns or noun phrases - right??

BTW, what the heck is a fused relative pronoun? One that's about to explode?
Well you actually bring up an interesting point. I have read various articles on appositives, and unfortunately, they provide different answers. Some say that an appositive has to be a noun phrase; however, some also say that it is usually a noun phrase but can also be an adjective phrase...When I'm left with a situation like this, I'm apt to go with what I feel is common sense, or change the definition to suit the sentence being analysed, haha, which makes life slightly easier.

And yes, the dummy 'it' makes the sentence slightly more difficult to analyse. But I'm not going to comment on whether the phrase can be in apposition to useful; I'll let you make up your own mind on this one, unless you have a grammar book, which has a definite answer, which you may wish to share with my puzzled self.
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