My First Question:
As far as I know, after the phrases like "many of", "some of" and "all of", we can't use a noun without the article. For instance, we cannot say "All of people are unintelligent", we have to say "All of the people are unintelligent" if we want to use the phrase "all of" even if we are talking about all people who are alive. Am I right? Can I say "All of the people", "Many of the men", "Some of the women" etc. if I am talking about all people in the world, many men among all men in the world and some women among all women in the world etc.? I know that I can say "All men", "Some people" etc without using the word "of" by the way, but I wonder if I can say those phrases like "all of the" instead. I also know that I can use those phrases which include the phrase "of the" when I talk about a specific group of things like in "All of the players of the American team are very athletic"(Here I am referring to the players in the American national basketball team while watching a game). But, as I said I want to know if can use those phrases which include "of the" for referring to things generally. I mean, when I talk about all basketball players in the world instead of all basketball players in the American team, can I say "All of the basketball players are very athletic"?
My second question:
What about the sentences where we use percentages? If I am talking about all people in the world generally, can I say "50% (fifty percent) of people are unintelligent", or do I have to say "50% of the people are unintelligent"?