push-down的用法和樣例：
詞匯搭配
- push down 下推
- push-down register 后進先出寄存器...
- push-down nesting 下推嵌套
- push-down store 疊式存儲器
- push-down tape 下推帶
- stack push down 堆棧壓入
- push-down list 后進先出表
- push-down stack 下堆棧
- push down queue 后進先出隊列...
- push-down storage 后入先出存儲器...
- push-down queue 下推隊列, 下推排隊...
- push-down automaton 排隊式自動機...
- push-down transducer 下推翻譯機
- push down storage 下推存儲器, 后進先...
- push down stack 下推棧
- push-down memory 后進先出存儲器...
- push-down transformer 下推變換器
