No matter which country you go to, you must fill out an entry or departure form.
As you all know, sometimes people forget or don't know, so I'm posting this here.
When you receive the immigration form, please fill it out in English and capital letters only.
It must be written in correct form. Write roughly and do not use lowercase letters.
If you are not familiar with English or are traveling alone and don't know much, ask or ask the
person next to you.
That's what all Koreans say.
When entering the country, you must report if you have more than $10,000 in dollars, duty-free goods worth more than $300, or more than 20 cartons of cigarettes. However, Korean cigarettes are much,
much cheaper here, so there would be no reason to bring them.
Anyway, if the above applies, you must report it.