This is an unprecedented disaster, but also an unprecedented national rescue operation.

这是一场空前的灾难，也是一场空前的全国救援大行动。

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The 2005 hurricanes caused an unprecedented disaster for the city and surrounding communities.

2005年的飓风给这座城市及周边地区造成了前所未有的灾难。

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In this unprecedented disaster, people's lives become so fragile, however, have become so stubborn.

在这场空前的大灾难中，人的生命变得如此脆弱，然而，也变得如此顽强。

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"We are dealing with a massive and potentially-unprecedented environmental disaster.

VOA: standard.2010.05.02

I'll close by saying this: This oil spill is an unprecedented disaster.

WHITEHOUSE: Deepwater BP Oil Spill: Presidential Press Conference

Now, I think the American people are now aware, certainly the folks down in the Gulf are aware, that we're dealing with a massive and potentially unprecedented environmental disaster.

WHITEHOUSE: President Obama Speaks on NYC Incident and BP Oil Spill in Louisiana | The White House

There were a lot of people that said, 'Oh, you're taking too long, '" the mayor said, but he called the results "a remarkable achievement, one that we expect will become a textbook case of innovation, resourceful and effective response to an unprecedented natural disaster.

WSJ: NYC post-Sandy home repair program passes 20K mark