Contoured
a. 波状外形的
🗣️ 情景例句
Do you feel like going to the cinema?
你想去看电影吗？
Bind the sack before it be full.
做事应适可而止。
The further off this solid obstruction, the longer time will elapse for the return of the echo.
固体障碍物越远。回声返回所用时间就越长。