Change the following examples into middle dictation : The eating utensil with prongs was rejected by the extremely youthful person.
Do you mean to change the examples into "middle diction"? Diction refers to word selection. If that is your question, it seems logical to me that the sentence can be changed in one of the following ways:
The child refused to use the fork.
The child turned down the fork.
Middle diction is the equivalent of colloquial speech, which is everyday language, different from formal language typically reserved for formal papers such literary analysis. Your example illustrates pretentious or bombastic language because the ideas expressed can be conveyed in much simpler words.