1. With scarcely a glance at the items, the clerk sweeps them across an aperture, where a special marking on each item is scanned by a low-powered laser beam inside the machine, connected to a remote computer.
    收款员几乎不看商品，只是把商品从机器上的孔眼处一扫而过，机器里的低能量激光对商品上的一个特殊标志进行扫描，这台扫描机与另一台电脑相联。

2. Nearly 100 years ago, the astronomer, Schiaparelli, thought the marking to be canals.
    而大约在一百年前天文学家夏帕雷里认为,这些条痕是运河.