Is "you think" a parenthesis ? Or it is a subject and a predicate of a object clause which in an attributive clause?

Question

Look at this sentence -

If you are prepared for something that you think is going to happen, you are ready for it.

I parse it like this :

if you are prepared for something
you think that is going to happen,
you are ready for it.

I think "you think" is an subject and a predicate in a attributive clause. In my mind, if "you think" is a parenthesis, there should be a comma before and after "you think" respectively. Is it right?

Answer 1

The way I read it, it's a relative clause. Here's the non-relative version:

You think something is going to happen.

Let's make it into a relative clause by relativizing something. This will leave behind a gap in the sentence where something is right now, indicated below with an underscore notation ___. We'll use the relative pronoun which to link something in its new location to the gap inside the relative clause:

something [ which you think ___ is going to happen ]

This noun phrase containing the relative fits inside the larger sentence:

If you are prepared for [ something [ which you think ___ is going to happen ] ], you are ready for it.

This is what some would call a restrictive relative clause, so it should not be set off with commas, nor should it be pronounced like a parenthetical. In the terms used by The Cambridge Grammar of the English Language (CGEL), it would instead be called an integrated relative.

Because it's an integrated relative clause and the gap isn't in subject position, we can delete the relative pronoun which. If we do, we can optionally insert the subordinator that, letting the reader know that we have a subordinate clause:

If you are prepared for [ something that [ you think ___ is going to happen ] ], you are ready for it.

But the sentence is also okay with neither which nor that:

If you are prepared for [ something [ you think ___ is going to happen ] ], you are ready for it.

This sentence is okay, too.

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It's possible to parse it your way, too, if you start from this non-relative clause:

Something is going to happen.

Again relativizing something, we get:

something [ which ___ is going to happen ]

And then we could again delete which and insert that, ending up with your sentence (sans parenthetical):

If you are prepared for [ something that [ ___ is going to happen ] ], you are ready for it.

After which you can insert the parenthetical:

If you are prepared for [ something that [ (you think) ___ is going to happen ] ], you are ready for it.

But although this parsing is technically possible, I don't think it's how most people would read the sentence. (Here I've chosen parentheses rather than commas, as in Codeswitcher's answer.)

So if you don't want to change how people are reading it, don't insert punctuation.

Answer 2

Agreed to toandfro's comment. In my opinion too, it isn't parenthetical. Though the sentence makes sense after removing you think. However, this is not an in-depth analysis of syntax of the sentence but here is what I can think of.

Think about the situation where you are simply following the order or instruction (which you simply believe and don't think), the meaning may change there.

Example: Let's talk about the weather department's instruction. You are in the halfway to New York City driving and you hear the warning from the department that a storm is very likely to hit the area you are reaching in 20 minutes or so. You then, simply prepare yourself for something (storm) that is going to happen You simply find some safe place until the danger is gone. In this case, you did not think but simply followed.

On the other hand, there are many cases, where your gut feeling says that something is going to happen and you, maybe against everyone's opinion, start preparing for that something which you think is going to happen. There you think makes utter sense.

Answer 3

As used here, it is not usually a parenthetical.

But it can be. Consider:

If you are prepared for something that (you think!) is going to happen, you 
are ready for it.

I actually write sentences like that all the time, but I'm a psychotherapist and am often disambiguating between reality and people's perceptions of reality.