lǎo / shī / xiān / jiǎng / jiě / èr / jìn / de / jī / běn / yuán / lǐ / zài / jiè / shào / shí / liù / jìn / zhì

老师先讲解二进的基本原理，再介绍十六进制。

The teacher first explained the basic principles of binary, then introduced hexadecimal.