Zài / wēi / fēn / jǐ / hé / kè / shàng / lǎo / shī / jiè / shào / le / xiān / wéi / cóng / de / jī / běn / gài / niàn在微分几何课上,老师介绍了纤维丛的基本概念。In the differential geometry class, the teacher introduced the basic concept of a fiber bundle.