Mesolithic
n. 中石器时代(旧石器时代与新石器时代之间的时代)
🗣️ 情景例句
The advanced class starts at ten o'clock.
高级健身课十点钟开始。
Last year I studied sociology and political science in school.
去年，我在学校攻读了社会学和政治学课程。
Don't forget to keep in touch.
别忘了保持联系。