A piece of work: A remarkably difficult, malicious, unpleasant, or objectionable person. Also, If you say that someone is a piece of work, you mean that they are very surprising, unusual, or impressive.
Etymology: An obnoxious individual. Originally this expression simply referred to something that had been created, and often in an admiring fashion. Shakespeare so used it in Hamlet (2.2), “What a piece of work is a man! . . . the Paragon of animals.” In the first half of the 1900s the term began to be used sarcastically and contemptuously, as in, “Lulu finally had to take her out of the room. Piece of work she is” (David Baldacci, Hour Game, 2004). A documentary film opening in June 2010 was entitled “Joan Rivers: A Piece of Work,” alluding to her often insulting comedy.
中文释义：“A piece of work”这个短语一般适用于两种场景：1、表示难搞的人或难搞的事情。该意思在影视剧里面应用得比较多，虽然本身没有侮辱的意思，但是也体现出了一点不友好；2、表示伟大的杰作或厉害的人物。work可以用来表示作品、工艺品、画作等，例如：It’s amazing to see such a piece of work in the French gallery. （在法国画展看到这样的一幅作品非常令人惊讶）。也可以用来表示一个人很厉害，例如：Mike is really a piece of work. He just finished the work himself. （Mike真的了不起，他自己完成了那项工作）。
1、go to pieces “支离破碎”“一片狼藉”
2、be a piece of shit/crap “一团糟”“不值得一看”
3、be still in one piece “顺利结束旅行”“安然度过了困难的情况”