Based on the level of respect or formality, you can say "He is out of town" in Korean in 3 ways:

• Informal: geu-neun yeogi eopseo (그는 여기 없어), geu-neun i dosi-e eopseo (그는 이 도시에 없어)
• Formal: geu-neun yeogi eopseoyo (그는 여기 없어요), geu-neun i dosi-e eopseoyo (그는 이 도시에 없어요), geu-neun yeogi eopseupnida (그는 여기 없습니다)
• Very Formal: geu-bun-eun i dosi-e eopseusipnida (그분은 이 도시에 없으십니다)

- he (subjective): geu-neun (그는), geu-bun-eun (그분은)
- town: maeul (마을), dosi (도시)
- out of town: yeogi eopda (여기 없다), i dosi-e eopda (이 도시에 없다)

Please refer to How to pronounce Korean Alphabet for the English pronunciation in this answer.