He was sent to a labor camp and served five years.
Tips
culture
劳改 is short for 劳动改造 (reform through labor), the term used in the PRC from the 1950s for the penal labor of convicted prisoners.
register
劳改 belongs to the history of the penal system. In contemporary Chinese it still refers colloquially to prison labor, though the formal term 监狱 (prison) is more neutral.