Here's why:
* Verbs are already flexible: Verbs already have various forms to express tense, aspect, mood, and voice. These forms are well-defined (present, past, future, present perfect, etc.).
* "Prolonged" is ambiguous: It's unclear what "prolonged" means in this context. Does it refer to:
* Duration: A verb form that emphasizes a longer action?
* Emphasis: A form that makes the action seem more important or drawn-out?
To understand what you're asking, we need more context. Could you please rephrase your question or provide an example of what you mean by "prolonged form of a verb"?