Since the classes are conducted in Hebrew and I get about 60% of what is being said, all I can give you is my understanding of verb tenses as of today. Tomorrow, it may change.
Neefal is a form, I use when I want to speak in passive voice. The package was sent.
Pe'al is what I use when I change the form from passive to active. I sent the package.
I do it on that exam and it is counted right... hot dog for carton!
Question: Do Israeli girls converse in Shebrew?
But Nefal, while it is often passive, can also be reflexive. For example, you can say ani nishmar, and it means either “I am guarded,” as in someone is guarding me, or “I am being careful,” as in I am guarding myself. For this, Hitpael would serve as well for this reflexive usage, but lacks the ambiguity. Ani mishtamer is “I am guarding myself.” Period. No other meaning is possible. Paul, on the other hand, is unambiguous. Ani shamur means “I am guarded” as in somebody else is guarding me and no room for reflexive doubts. So you can be either very precise using other forms and voices, or deliberately vague using Nefal.