manual telephone exchange
常见例句
- A standard element of technology that can be traced to 1878 and the invention of the manual telephone exchange, the jack is apparently going the way of the floppy disk and the folding map.
這一標準技術元素可追溯至1878年，來自人工電話交換系統。 它似乎正在步入軟磐和折曡地圖的後塵。 返回 manual telephone exchange