BBC news 2010-05-01 加文本

1.But it's unclear what promises the US has made to the Palestinians to guarantee there will be no further unilateral Israeli actions that undermine the process.

参考翻译：但是，美国作出了什么样的承诺以保证以色列不会采取单方面的行动来破坏和平进程，这一点并不清楚。

结构分析：it's unclear中的it是形式主语，真正的主语是后面的what promises the US has made to the Palestinians。to guarantee表示目的。there will be no further……是guarantee的宾语从句。that undermine the process是定语从句，修饰actions。

2. Strong winds are pushing the oil over boom set up to protect fragile wetlands and three other states are also threatened with  environmental disaster.

参考翻译：大风已经使浮油越过了用来保护湿地的水栅，其他三个州也面临着环境灾难的威胁。

结构分析：这个句子包含两个并列的句子：Strong winds are pushing the oil over boom and three other states are……
set up to protect是过去分词作后置定语，修饰boom。

3.We continue to urge BP to leverage additional access to help lead the response in this effort because it's clear that after several unsuccessful attempts to secure the source of the leak, it's time for BP to supplement their current mobilization as the slick of oil moves towards shore.

参考翻译：我们继续敦促BP石油公司提供更多帮助，对这次行动作出回应。因为很明显，针对控制石油泄漏源头的几次行动均已失败告终，现在，由于漏油已经向海岸移动，BP石油公司应该增加机动性。

结构分析：主句是前面的部分，because说明原因。it's time for sb to do sth是某人做某事的时候了。as the slick of oil moves towards shore是时间状语。