tā / zài / yán jiū shēng / jiē duàn / xuǎn zé / le / shuāng zhǔ xiū / zhè / ràng / tā / xū yào / xiū dú / gèng duō / de / xué fēn

他在研究生阶段选择了双主修，这让他需要修读更多的学分。

He chose a double major during his graduate studies, which required him to take more credits.