tā / zài / xīn / lǐ / xué / kè / shàng / fēn / xī / le / shī / nüè / shòu / nüè / xíng / wéi / de / shè / huì / gēn / yuán他在心理学课上分析了施虐受虐行为的社会根源。He analyzed the social roots of sadomasochistic behavior in his psychology class.