This is the 155th most frequent Korean word.
사람이
"사람이" means "person" or "human," with the subject marker "-이" attached.
The word "사람이" here is the subject indicating 'the people' who are many.
사람이 많아서 자리가 없어요.
There are so many people that there are no seats available.
The word "사람이" represents the subject, asking if 'a person' made this.
사람이 뭐 이런 걸 만드나요?
Does a person create something like this?
The word "사람이" is used as the subject, questioning 'the reason why people live.'