No one yet knows what made Derrick Bird attack these people, who seem to have included his twin brother and colleagues from work as well as total strangers, before killing himself.

目前还没有人知道什么让Derrick Bird在杀死自己前向这些人们发动袭击，其中似乎还包括他的孪生兄弟和同事以及完全不相干的陌生人。

youdao

A twin-engine aircraft has crashed in North-East Brazil, killing all 16 people on board.

一架双引擎飞机在巴西东北部地区坠毁，舱内16人全部死亡。

youdao

Late Monday, twin explosions struck a busy market in the eastern city of Lahore, killing nearly 50 people, mostly women and children.

VOA: standard.2009.12.09