A list of elements that make a presentation good would be the following,
The goal of the presentation is crystal clear
All the information is relevant to the topic
It includes comparisons and contrasts
It includes visual representations (picture, charts, graphs, etc)
It meets the needs of the current audience.
It provides easy and clear instructions on contacting you.
All of these elements are a must-have for every presentation in order for it to be effective.
Referring to a presentation that is currently missing one or more of these elements, I would add these elements and focus on making the presentation as specific and personal as possible in order to attract the targeted audience and for the presentation to be more engaging to them.
A decent high school paragraph should at least have 6-8 compound-complex sentences or just complex sentences. I hope this is the answer you are looking for! :)
