1.It lets you shop as normal and then scans what you have bought as you leave the store.
as normal正常
He wasn't quite as perky as normal.
他并不像往常那么高兴 。
2.There is no waiting in line, no cashiers, and no being held up by slow customers, credit card transactions or waiting for change.
hold up耽搁
Continuing violence could hold up progress towards reform.
持续的暴力活动可能会阻延改革的进程 。
3.The grocery and convenience store markets are extremely tough nuts to crack.
tough nuts to crack难处理的事物
Cultural aspects are always tough nuts to crack in translation, especially in drama translation.
牵涉文化层面的翻译往往比较棘手,尤其是在话剧翻译中 。