Particular question about "of which"

Question

Do you have the forms of which I speak in order to make this renewal official?

In this sentence , why "of which" is used and why?

This sentence appears in Smosh video.

The link is https://www.youtube.com/watch?v=f1e38s1feKg.(It's at 1:30)

Answer 1

In a comment under the question, you said this:

I know that which refers to the "forms" but "of" is the thing that is making me [confused].

Given that you aren't questioning the use of which itself in the sentence, you can consider the following two simplified versions of the sentence:

1. Do you have the forms which I speak of?
2. Do you have the forms of which I speak?

They are both grammatical and mean the same thing—it's just that in the second version the preposition has been moved from its position after the verb to a position in front of it.

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At one point, a myth was circulated that you shouldn't end a sentence with a preposition. For some reason, it caught on and became taught as fact by many people.

In reality, where the preposition is placed is just a matter of style and personal choice.

You can read more about this at "Ending a Sentence With a Preposition" by Mignon Fogarty.

However, when it was thought to be wrong, the so-called problem was addressed by moving the preposition from the end of the sentence to a position in front of the verb.

Borrowing from the linked article, here are a couple of sentences with the location of the preposition changed:

What did you step on?
On what did you step?

I want to know where he came from.
I want to know from where he came.

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Finally, consider this sentence:

She displayed the good humor she’s known for.

Simply moving the preposition here wouldn't work:

✘ She displayed the good humor for she's known.

In order for this to be grammatical, which has to also be employed:

✔ She displayed the good humor for which she's known.

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Note that the original version of the sentence in the question could also be rephrased to express the same thing in a way isn't quite so tricky to parse.

For instance:

Do you have the forms of which I speak in order to make this renewal official?

→ Do you have the forms I'm talking about that would make this renewal official?

Answer 2

They are asking for the forms, and they are going to be speaking about those forms in order to make the renewal official.
"Of which" refer to the forms here.

Answer 3

Of which was used because of its formality. Outside of a formal context, this construction can sound affected.

The somewhat formal construction of preposition + which can often be replaced by a relative adverb (why, when, where) or relative pronoun (which, that, who, whom, whose). Relative adverbs, like relative pronouns, can introduce a relative clause. Clauses with a relative adverb supply adverbial information and can be either restrictive or non-restrictive. The sentences in the first two groups below each contain a restrictive relative clause.

Relative Adverbs

Why > for which

The reason why the war began is still unknown.

The reason for which the war began is still unknown.

When > on/in which, at which

The year when the drought began was very hot.

The year in which the drought began was very hot.

Where > in which, through which

That hotel where you lost your passport is known for having a lot of crime.

That hotel in which you lost your passport is known for having a lot of crime.

Relative Pronouns

Whose > of which

Tokyo is a city whose attractions are many.

Tokyo is a city of which the attractions are many. (can sound affected)

Which, That > to which, on which

The country which you are going to is simply unsafe.

The country to which you are going is simply unsafe.

Collectible dolls, which she spends most of her money on, can be pricey.

Collectible dolls, on which she spends most of her money, can be pricey.

As (preceded by such or same) introducing a restrictive relative clause

In the airport, the VIPs enjoyed the same privileges as diplomats.

Her manners are such as a princess has.

Some sentences with preposition + which can be simplified, usually to a less formal structure.

The visa with which you were to go to America has expired.  (rather formal)

You were to go to America with this visa, but it has expired.

The visa that you were to go to America with has expired. 

The visa you were to go to America with has expired.        

Your American visa has expired.



Do you have the forms of which I speak in order to make this renewal official?

Do you have the forms that I spoke of, the ones to make this renewal official?

Do you have the forms I mentioned, the ones to make this renewal official?