안녕하세요,
My question is about the plural marker -들. Can it be used besides of when talking about people? I hardly ever hear Koreans say 차들, 집들, 책들 etc.
For example if someone would ask me “what did you buy?”
And I would want to answer with “I bought books”
Could I write “책을 샀다/책들 샀다”...or?

See a translation

@beyzaz It makes plural nouns by adding "들" to nouns. ex) 강아지 (puppy) -> 강아지들 (puppies) However, we seldom use the plural nouns as it is clear in most cases whether the noun is singular or plural from context. When we say, 'She has two kids in Korean : 그녀는 두 명의 아이가 있다', you know the noun, 'kid' is plural even though we do not change it to a plural form, kids.

In English, it’s required to use plurals when the quantity is more than one. In Korean, “들” is only used to make a plural noun when you want to stress that there is more than one. All other times, it’s not necessary to change a noun into a plural, since all Korean singular nouns can already act as plurals.

e.g.
머리카락이 많이 빠졌어요. I lost a lot of hair.
저는 원숭이를 좋아해요. I like monkeys.
지우개를 몇 개 샀어요? How many erasers did you buy?

Notice that in these examples, it’s perfectly clear that the speaker means the plural. It wouldn’t be necessary to say “I lost a lot of hairs.” It would be strange to say “I like a monkey.” Or, “How many eraser did you buy?” It’s not necessary to change regular nouns into plurals unless you want to stress that there are more than one in your sentence.