N이나/나¹
It is used to indicate that only one of the listed items is selected.
When the noun ends in a consonant, use ‘이나’, and when the noun ends in a vowel, use ‘나’.
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N이나/나² Choose the one that is easy to choose though it is not the best choice among many
N이나/나³ Roughly ask how many in numbers or how much in quantity.
N이나/나³ Express the speaker thinks that the quantity or the degree is large or high