BBC news 2010-04-09 加文本

1.But at a news conference here in the capital, they admitted there were concerns that the president was trying to rally his supporters in the south of the country in order to fight back.

fight back抵抗, 反击

例句：They fought back heroically.
      他们英勇反击。

concerns that后面是同位语从句。

2.Rescue teams at the scene say they have come across pockets of toxic gases caused by decomposing waste.

come across偶然发现, 偶然遇见

例句：I came across him in the street yesterday.
      昨天我在街上无意中碰到了他。

另外一个意思：

出现在脑海中, 留下印象

例句：A good idea came across my mind.
      我忽然想到一个好主意。

3.This is what has been slowing down their work.

slow down(使)慢下来

例句：The machine slowed down and stopped.
      机器逐渐减慢了转速, 终于停住了。

      You have to slow down your car at the crossing.
      在十字路口, 你得放慢速度。

4.The court in the predominately Muslim country said that it was a woman's personal choice and that if she was compelled to wear a veil, this would amount to a violation of fundamental rights.

amount to意味着

例句：His words amounted to a threat.
      他的话实际上是威胁。

5.One of the scientists said the discovery opened up a new chapter in the history of humankind.

open up展开,打开,开发,揭露,开始

例句：They decided to open up a business in the town.
      他们决定在城里开展业务。