lǎo / shī / yòng / tú / piàn / xiàng / xué / shēng / jiè / shào / huán / jié / dòng / wù / de / shēn / tǐ / jié / gòu

老师用图片向学生介绍环节动物的身体结构。

The teacher used pictures to introduce the body structure of annelids to the students.