Is this structure correct?
The book whose information I wanted was missing

No, it's not good. This would be better:

The book containing some information I wanted is missing.


PaulM

The clause "why he came late" in "That was the reason why he came late' is an adverb clause or not?

That was the reason [why he came late].


No, it's a relative clause. It's modifying the noun "reason".

PaulM

What is a relative clause?
Is "why" a subordinating conjunction?

A relative clause is a subordinate clause whose main function is that of modifier to a noun, for example:

I've met the woman [who wrote it]

The noun "woman" serves a antecedent for an element within the relative clause, in this example the relative pronoun "who". We understand that the woman wrote it.

In your example, "why" is NOT a subordinating conjunction, it is an adverb.

PaulM

Thank you but how is "why" an adverb?

I think you are asking why the word "why" is an adverb and not a subordinating conjunction.

The answer is that conjunctions do nothing more than connect 2 clauses, whereas relative adverbs like "why", "when" and "where" play a role in the relative clause, usually as adjuncts, for example:

In "That was the reason why she got angry", "why" refers back to "the reason" in the main clause, so it actually does something other than join the two clauses. In that example, "why" is functioning as an adjunct of reason.

"Why", and other wh words like "when" and "where" deal with adjuncts of reason, time and place, all matters that adverbs typically deal with.


PaulM

Sir, Actually i was reading m.c.qs in a grammar book and then i saw the following m.c.q
That was the reason why he came late. The clause 'why he came late' is a/an
(a)Adverb (b)Adjective clause
(c)noun clause (d)Adjective
Can you tell me which option is correct with a 'reason'?
The book says it is an "adjective clause". Is it true?
Kindly tell me.

Well, Emma, as I told you before, it's a relative clause.

Some very basic grammar books call a relative clause an 'adjective clause' simply because it modifies a noun, so in way your book is correct. But in modern grammar we don't call it that because it's not a very good description of the clause.

PaulM

It's an adverb clause

I am satisfied with your explanation but can u tell me plz that which option should we mark as right.plz tell me

Adverb clause or adjective clause???