I should only add a noun behind the “of which”, right? or am I wrong?

Question

Recently, I saw a definition describing "blind copy:"

A copy of a letter or the like, the original of which bears no evidence that the copy was sent to some other person.

In the expression above,is it correct to place a verb behind "Of which?"

I also saw a former example about "Of which" that writes like

The restaurant of which service satisfied me

At any rate,i just cannot get first definition sentence. I mean, why they use verb behind it rather than a noun. or the word behind the "of which" can be either a verb or a noun?

Answer 1

In the clause following the comma in your first example, "the original" is the subject, "bears" is the predicate, and "of which" is a prepositional phrase that acts as an adjective (for "the original").

The complete sentence would be

[A blind copy is] a copy of a letter or the like, the original of which bears no evidence that the copy was sent to some other person.

The second sentence you gave actually does not sound grammatically correct to me. To what does "of which" relate? It seems to relate to "service", but then it ought to be

The restaurant, service of which satisfied me.

Prepositional phrases usually follow the noun they define. In that sentence "of which" is the same as in your first sentence, a prepositional phrase defining "service".