When to use last month in Korean
Korean: 지난달[ ji-nan-dal ]

When to use it
"Last month" means the month before this month. Use it to talk about something that happened one month ago. In Korean, 지난달 is a common time word you can use in everyday sentences.
Example sentences
지난달에 새 집으로 이사했어요.
We moved to a new house last month.
저는 지난달에 학교 축제에 갔어요.
I went to the school festival last month.
지난달에 공원에서 자전거를 탔어요.
I rode a bike in the park last month.
엄마는 지난달에 새 냉장고를 샀어요.
Mom bought a new refrigerator last month.
우리는 지난달에 부산으로 여행을 갔어요.
We traveled to Busan last month.
지난달에 친구를 우리 집에 초대했어요.
I invited a friend to our house last month.