1. The shopper only needs to place all the items on the conveyor belt at the checkout counter.
    顾客只需把所选物品一古脑全放在传送带上，

2. As the grocery items moves along the conveyor belt, the checker passes each item over a glass plate in the counter top, making sure that the UPC symbols can be read by the laser beam under the glass.
    食品杂货经传送带传到收款员跟前，收款员随即将每一物品搁在柜台上的一块玻璃板上一扫，好使板下的扫描机阅读条形码。