This is the 914th most frequent Russian word.
месяце
"Месяце" is the prepositional case form of "месяц," meaning "month" in English.
Here, "месяце" is the prepositional case of "месяц", used to indicate the time reference "in the last month".
В прошлом месяце я начал заниматься йогой.
Last month, I started practicing yoga.
In this question, "месяце" is also in the prepositional case, used to inquire about a specific month when something will occur.
В каком месяце будет отпуск?
In which month will the vacation be?
In this sentence, "месяце" serves in the prepositional case, indicating the time reference "in the next month".