BBC在线收听下载:奥巴马将向喀麦隆派出300名军人

短语讲解：

1. A new study has found the Ebola virus can linger on in male survivors for at least 9 months, much longer than previously thought.

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。

2. Police in Mexico have arrested a 14-year-old boy who was recruited on Facebook to carry out a contract killing.

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. It sets out basic air safety procedures in the skies above Syria.

set out 出发; 着手; 动身
例句：He set out to conquer the literary world of London.
他决心赢得伦敦文学界的赞誉。

4. They say it's so well preserved that they'll be able to conduct a detailed analysis of the remains.

be able to 能够; 能
例句：He will be able to take up his normal routine shortly.
他不久就能处理日常事务。

5.  But its lower back was covered in short hedgehog-like spines and some tough scales helping it to ward off predicators such as the small dinosaurs that shared its habitat.

ward off 抵挡; 避开
例句：I try to ward off fatigue by resting as much as possible.
为了防止疲劳，我尽可能多休息。

6. He was nicknamed the chameleon because of his changing political affiliations.

because of 因为，由于
例句：All the planes were socked in yesterday because of the thick mist.
由于雾大，昨天所有的飞机都停飞了。