"My mother buys clothes."
Translation:Kūʻai koʻu makuahine i ka lole.
Aloha e @Oceanic2 , ʻae this can be confusing at first, but this concept is actually closer to English than it seems.
Compare the two sentences in english:
My mother buys clothes.
My mother buys food.
with the following two senences:
My mother buys the clothes.
My mother buys the food(s).
The first two sentences describe, very generally, any clothes and any food (and does not necessarily imply quantity). The second two sentences describe multiple pieces of clothing and food(s) which are known based on context of the conversation. In english we can do this be adding and removing "the" and keeping the common noun in the plural.
BUT in Hawaiian, you are required to have a ka/ke/kēia/kou/etc. - class of descriptive particle before the common noun-like subject you are talking about. So instead in Hawaiian, you can use ka/ke to refer to something "in general" or nā to refer to the plural of something specific known by context in the conversation.
I hope this helps a little bit. Going into any Polynesian language from the English/Western language perspective can be challenging at first, but will become more clear.