Someone threw a birthday party with several dozen guests before. When you are describing the guests, I think you can use these sentences:
Dozens of people came to his birthday party. Many of them were his friends.
My question is, when you want to write this in one sentence, which sentence can you use?
Dozens of people came to his birthday party, many of them his friends.
Dozens of people came to his birthday party, many of them being his friends.
I am not sure whether you should use "being" after "many of them." Can the word "being" be omitted?