You would add key events. Summaries are basically condensing down a story or a book or an essay so it’s shorter, so To get the idea of the book you need to have the key events.
False - there is no subject-verb disagreement as "...my siblings are coming to the party" is correct. It is plural as in "are" because the nearest subject is plural as in "my siblings".
All of the above. You want to know how happy are employees, how many employees are there and if the is a spike in hiring and finally the goals so you know what the company’s purpose is.
