Clause between comma [duplicate]

The narrator, in the quote, said that things turned out to be horrible.

According to the question I previously posted, this parenthetical prepositional phrase "in the quote" is made possible by whiz deletion. But when I applied whiz deletion to it, it turned out to be a disaster.

The narrator, who was in the quote, said that...

Surely, what I was trying to say was that narrator said something in the quote, not that narrator was PHYSICALLY in the quote.

Here is another example.

They, (who were) after so much thinking, finally decided.

Now it is just not right.

So my another interpretation was that there was an absolute phrase with "being" deleted, but it brought about the same result. You can see what I mean if you substitute who was/were for being.

So, why is it possible to use parenthetical prepositional phrase in the middle of sentence? Is there anything deleted?

Solution 1:

The narrator, in the quote, said that things turned out to be horrible.
They, after so much thinking, finally decided.

There is, as you suggest, no deletion in these two cases.

I suspect you have been misled by the position of the two preposition phrases (in the quote and after so much thinking) after two nominals (narrator and they). That is the ordinary position for a PP which modifies a nominal, so if these two PP modified these two nominals that is where you would expect to find them. In that case many linguists would say that the two PP should be parsed as relative clauses reduced by Whiz-deletion.

But in fact these PP do not modify the nominals; as you yourself recognize, that analysis is a disaster. The PP are 'adverbial adjuncts' understood to modify either the entire clauses to which they are attached or the verbs which head those clauses (the difference is irrelevant to this discussion). This may be clearly seen from the fact that the PP may be moved to different positions without changing the fundamental meaning:

The narrator said in the quote that things turned out to be horrible.
In the quote the narrator said that things turned out to be horrible.

They finally, after so much thinking, decided.
After so much thinking they finally decided.
They finally decided, after so much thinking.

Where you put the adverbial depends in part on what you want to emphasize and in part on the surrounding context—for instance, you don't want to put in the quote after horrible, because that suggests that things turned out to be horrible in the quote rather than in the events the narrator was talking about!