'What will Steven Smith put a wallet in his pocket'
Is there any explanation why this sentence is not acceptable?
Let us convert the sentence from interrogative mood into declarative mood:
Steven Smith will put a wallet in his pocket.
'what' is missing right? Question: How can we insert 'what' in the sentence? First we have to know what 'what' is. What is fronted in interrogatives that is an NP? Subject or direct object or indirect object.
'What' = S?
What Steven Smith will put a wallet in his pocket.
If what = S, then Steven Smith = ? An apposed restrictive NP? No, it is not possible.
What = indirect object? No; 'put' is never ditransitive.
--> What = DO
Where is a slot for a DO of 'put' in our declarative sentence?
Steven Smith will put _ a wallet in his pocket.
Steven Smith will put what a wallet in his pocket.
Steven Smith will put this a wallet in his pocket.
When a verb is followed by two NPs, one of them must be either an indirect object or an object complement that expands the meaning of the direct object.
Indirect object we can't have as I already said, since 'put' has no ditransitive uses.
'a wallet' = Objective complement?
1. [Steven Smith] [will put] [this] [a wallet] in his pocket. -- NP VP[NP NP Adv.P]
2. [Steven Smith] [will elect] [him] [president] in the conference hall. -- NP VP[NP NP Adv.P]
As we can clearly see,
formally the two sentences are identical. Why still #1 is :down:? No syntax without semantics, comes to mind. What does #1 mean?
I cannot see the way that 'a wallet' could possibly extend the meaning of 'what'. That is my concern and that is why I discard #1.
Conclusion:
what ≠ indirect object
what ≠ C
[what a wallet] ≠ NP
--> The sentence you proposed is wrong.
QED.