For three weeks a big operation went on to recover the wreckage from the sea bed.

一项大规模行动持续3周以从海床寻找残骸。

《柯林斯英汉双解大词典》

The USA was a big operation, very big.

美国本身是一宗大投机买卖，非常大。

youdao

They are preparing for a big operation.

他们在准备一场大规模的军事行动。

youdao

The rebellion has become increasingly violent. Worried by the growing security threat posed by the Maoists, the government is preparing to mount a big security operation called Operation Greenhunt to take out the insurgents.

VOA: standard.2009.11.04

For children, doctors sometimes fashion a new ear from the stiffer cartilage surrounding ribs, but it's a big operation.

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So it was very difficult to have a founder running a big operation.

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Callouts have gone up 40% since 2005, this is a big operation, a lot of people's lives are at risk here.

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