everything is so cheap.

答案：D；expensive昂贵的，cheap便宜的，都很具体，用来形容物品的贵或便宜；highly高地，副词，lowly低地，副词；high高的，形容词，low低的，形容词，两者都很抽象，用来形容价格或消费的高低等；题中的生活花费和价格都要用"高低"来表达，且系动词的后面都要用形容词形式，故选D．

扩展阅读：put away your book ... everything is possible ... everything will be ok ... everything has beauty ... everything is suck ... everything goes well ... everything changes ... everything is fake ... time is everything ...