VOA慢速英语:Obama: US, Saudi Arabia Have 'Extraordinary Friendship'

短语讲解：

1. It is close to the offices of the United Nations Assistance Mission in Afghanistan.

close to 离…近;与…关系密切;近乎;临近
例句：Nominal yields are close to historic lows.
名义收益率接近历史最低水平。

2. The general’s execution was reportedly carried out with an anti-aircraft gun as hundreds of people watched.

carry out 履行
例句：No matter what we do, we must carry out our duties.
无论干什么工作,我们都应履行自己的职责。

3. U.S. transportation officials say the Amtrak passenger train that crashed Tuesday night in Pennsylvania was traveling at more than 160 kilometers per hour.

more than 多于
例句：Common sense is worth more than learning.
普通的见识比学问更重要。

4. That is at least twice the permissible speed.

at least 至少
例句：In fact it requires at least n generators.
事实上，它至少要有n个元素。