短语讲解:
1.So, an increasing number of American schools are requiring students learn about these documents before they can graduate.
learn about 获得,学得; 得知有关…的消息
例句:He was deeply grieved to learn about his teacher's death.
他得知老师去世的消息,非常难过。
2.Since 2012, Kentucky, Arkansas and at least 12 other states put into effect such requirements.
at least 至少
例句:He's been away for at least a week.
他走了总有一个星期吧。
put into effect 实施; 实行; 使生效; 实现
例句:The bill was put into effect last month.
那法规于上个月生效。
3.Others are worried about the way Republican President Donald Trump and his supporters use their power.
worry about 担忧, 烦恼; 惦念
例句:Don't worry about him; he is a cheerful and elastic man.
别为他担心;他是个快活开朗的人。