yeogwon boksaboneun chekeu-in si yeonrakcheowa hamkke jechulhaeya haeyo.

You must submit a passport copy along with your contact information at check-in.

Breakdown of yeogwon boksaboneun chekeu-in si yeonrakcheowa hamkke jechulhaeya haeyo.

• ~은: topic particle
• ~와: comitative particle
• 함께: together
• 해야 하다: to have to

Questions & Answers about yeogwon boksaboneun chekeu-in si yeonrakcheowa hamkke jechulhaeya haeyo.

Why does the sentence use the topic marker 은 after 여권 복사본 instead of the object marker 을/를?

• 은/는 marks the topic, not the grammatical subject. Here, 여권 복사본 is the logical object of 제출하다, but it’s being topicalized: “As for the passport copy…”.
• Using 을 is also fine and a bit more neutral: 여권 복사본을 체크인 시 연락처와 함께 제출해야 해요.
• With 은, there can be a slight contrastive feel (e.g., “As for the passport copy, you must submit it…” possibly implying other items have different rules).

What exactly does 체크인 시 mean, and can I replace it with 체크인할 때?

• 체크인 시 literally means “at the time of check-in.” 시(時) is a bound noun meaning “time (when),” often used in formal/written language.
• 체크인할 때(에) means the same thing and sounds more neutral/natural in everyday speech.
• Both are correct. On signs or notices, 체크인 시(에) is very common.

Should it be 체크인 시 or 체크인 시에? Is there any difference?

• Both 체크인 시 and 체크인 시에 are acceptable. Adding 에 just makes the time marking explicit.
• In formal writing, omitting 에 after 시 is very common (e.g., 예약 시, 결제 시).

Can I say 체크인에서 to mean “at check-in”?