tā / zài / dà xué / zhǔ xiū / shí yóu huà xué / bì yè / hòu / jìn rù / le / yī jiā / shí huà / gōng sī他在大学主修石油化学,毕业后进入了一家石化公司。He majored in petrochemistry at university and joined a petrochemical company after graduation.