BBC在线收听下载:美国公布俄军越境袭击乌军的证据

短语讲解：

1. A government spokesman said the army was aiming to seize the site so that the international experts can carry out a thorough investigation into the cause of the crash.

carry out 执行; 进行
例句：They should also carry out some fundamental reforms.
这些政府也应该执行一些基础性的改革。

2. Government troops have made significant advances in the region near the area of countryside containing the wreckage and probably some remains of the victims on board Flight MH17, the Malaysian airliner which was blown up over rebel-controlled territory 10 days ago.

blow up （使）爆炸; 产生; 爆发; 发怒
例句：It did not blow up overnight.
它不是一夜之间爆发的。

3. The Dutch Prime Minister Mark Rutte has ruled out sending an international military mission to secure the site of the crashed Malaysian airliner.

rule out 用直线划掉; 宣布…不可能，排除…的可能性
例句：Can we rule out non standard solar models?
我们可以否定非标准太阳模型了吗？

4. Ten days after the plane was apparently shot down, forensic experts have not yet been able to start work.

shoot down 朝下射击; 击落; 击破…的论点
例句：These are missiles used to shoot down other missiles.
拦截导弹用于击落其他国家入侵的导弹。
be able to 能，会; 能够
例句：I admire the way she is able to shrug off unfair criticism. 
我很佩服她能对错误的批评意见不予理会。 

5. The group has recently stepped up attacks across a long and porous border between the two nations fighting against the Cameroonian military.

step up 加紧
例句：We must step up our vigilance. 
我们一定要提高警惕。 

6. Activists say Islamic State has taken control of an army outpost in the region a day after taking another army stronghold near the Islamist controlled city of Raka.

take control of 控制
例句：There must be someone who can take control of these naughty children.
应该有人能管住这些淘气的孩子。