Tired of standing in line? Wait a bit longer, and you may never have to again.

12. B    13. A    14. A    15. B
【解析】
本文是一篇说明文。文章主要介绍了亚马逊Go商店的智能购物车情况以及现在面临的问题和智能购物车的未来。
【12题详解】
细节理解题。由题干中的关键词“the smart shopping carts”锁定到第二段寻找答案，根据“These companies have added cameras and sensors (传感器) to the carts, and are using AI to tell what you’ve put in them.”可知智能购物车上增加了照相机和传感器，运用AI技术可以告知你购物车里放了什么东西，由此可知B选项为正确答案。
【13题详解】
细节理解题。根据题干中的关键词“Beshry”锁定到第三段寻找答案，根据“Beshry, co-founder of Caper, believes the technology to run Go is too expensive to use in a large-format grocery store.”可知Beshry认为把运用到Go商店的技术应用到一些正式的大的商店太昂贵了，由此可知A选项为正确答案。
【14题详解】
细节理解题。根据最后一段“Each time a business uses artificial intelligence and cameras, it raises questions about customers’ privacy and the effect on jobs.”可知，当提到AI技术和照相机时，公众最担心的是隐私问题和对工作的影响，故A选项“可能有人知道他们的隐私”为正确答案。
【15题详解】
主旨大意题。根据文章对智能购物车的介绍，可知整篇文章是在围绕智能购物车展开，根据第一段“Tired of standing in line? Wait a bit longer, and you may never have to again. Amazon has opened 24 of its Amazon Go stores, which use cameras and artificial intelligence (AI) to see what you’ve taken off shelves and charge you as you walk out.”可知运用了人工智能和照相机功能的智能购物车可以让你免去排队长时间等待的问题，结合选项，可知B选项“智能购物车可以让你省去排队”为正确答案。