There are three reasons for the public-sector unions’ thriving. First, they can shut things down without suffering much in the way of consequences. Second, they are mostly bright and well-educated. A quarter of America’s public-sector workers have a university degree. Third, they now dominate left-of-centre politics.
词汇
Thrive vi.兴旺发达;繁荣;茁壮成长
Consequence n.结果;后果;重要性 sequence 次序
Degree n.度;程度;度数(角的量度单位或温度单位);（大学）学位; to some degree 某种程度上 pursuit a master’s degree 读硕士
Dominate v.支配;控制;左右;在…中具有最重要(或明显)的特色;俯视;（在比赛中）占有优势
Domin 控制 ate 动词后缀—dominate 支配 predominant 主导的，盛行的
a predominance of female teachers in elementary schools
小学里女教师居多的现象
Politic adj.谨慎的;得当的;明智的v.(贬)从事政治活动 find it politic to do发现做某事是明智的
Union n.协会;联合会;(尤指内战时期的)美利坚合众国，美国;联合;结为夫妻
Shut down （使）（工厂、公司等）关闭，歇业，停业 shut up 闭嘴
句子主干
Three reasons for the public-sector unions’ thriving:
First, they can shut things down without suffering much in the way of consequences.
Second, they are mostly bright and well-educated.
Third, they now dominate left-of-centre politics.
写作借鉴
There are three reasons for my recommendations,first...,second...,third...
这个句子讲的是美国工会的组成，其实今日的五一劳动节就与工会有关，最初工人罢工争取八小时工作制，1889年7月，恩格斯宣布将将每年5月1日定为国际劳动节，以纪念这次伟大的工人运动。同时他还鼓励工人阶级要在每年5月1日都进行游行示威，使资本家同意工人们实现八小时工作制的诉求。1890年5月1日，西方国家的工人们纷纷走上街头举行示威游行与集会，争取合法权益。这一天后来成了如今五一国际劳动节。
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