Dnf
abbr. 未完成（did not finish）
🗣️ 情景例句
He worked his way through college.
他半工半读念完大学。
Do you often study history on Saturday?
你常常在星期六学历史吗？
has spent his lifetime studying active volcanoes and deep caves in all parts of the world.
花了毕生的精力来研究世界各地的活火山和探洞。