The boys were letting off fireworks.

那些男孩在放花炮。

《牛津词典》

People set off fireworks and tooted their car horns.

人们放起烟火并按响汽车喇叭。

《柯林斯英汉双解大词典》

A gang of boys were setting off fireworks in the street.

一帮男孩子正在街上放烟火。

《牛津词典》

Beijing's night sky was lit up by thousands of exploding fireworks to scare off evil spirits.

VOA: standard.2010.02.14

The late goal sent the Libyans into jubilation, as they set off fireworks in the stadium.

BBC: SPORT | Football | African | Libya 2-1 Egypt

Or letting off fireworks to stop them swooping on to landfill sites - one of their favourite eateries?

BBC: MPs declare war on aggressive seagulls

In Indiana, fire officials are cautioning against shooting off fireworks, with some counties banning their use by residents.

WSJ: Midwest's Dry Spell Threatens to Intensify