Polereverser
换向器
🗣️ 情景例句
Thanks, Mom.
谢谢，妈 。
To operate a steam locomotive
驾驶蒸汽机车
Modern machines can make the copy bigger or smaller, lighter or darker and copy onto both sides of the paper.
代机器可以放大、缩小、制作较亮的或较暗的复印件，也可以在纸的两面复印。