Their captors told them they would be killed unless they cooperated.

抓住他们的人说如果他们不配合就杀掉他们。

《牛津词典》

They would be killed if the car went over the cliff.

如果汽车翻在悬崖下， 他们就会丧命。

youdao

If he did not pull it, and the rocket exploded, they would be killed.

如果他不把它和火箭发生爆炸，他们将被杀死。

youdao

Eventually the doses of radiation should do so much damage to the cancerous cells that they would be killed.

BBC: One test may 'find many cancers'

And no one came to help him as he bled to death on the pavement because they were afraid they would be killed, too.

NPR: Journalists Dodge Danger to Report on the Dead

Those who escaped weren't simply survivors, she argued, they were hostages who feared they would be the next killed.

WSJ: After Tragedy, City Suffers Second Trauma Over Victims' Fund