经济学人下载:一周要闻 美国掀反垄断调查 脸书被罚50亿美元 波音季度亏损29亿

Public officials can finally be held accountable for their actions.
终于要对政府官员实行问责了。 

2.in a decade 十年内

Power generation fell for the first time in a decade.
发电量十年来首次出现下降。

3.pay down 偿还；支付

I used it to pay down some credit cards.
我用来付信用卡帐了。

4.social media 社交媒体

We have all witnessed the power of social media.
我们见证了社交媒体的实力。