Pushdown
推下; 后进先出方式
🗣️ 情景例句
study for my math final.
温习数学 准备期末考试。
If you always say NO,never be married.
常常说“不”字，永远难结婚。
I guess she's gone to visit some friends in another town.
我猜她是去别的城镇看朋友了。