More than nine hundred people have died in the fighting. 900多人在这场战斗中丧生。

Nearly 2,500 have died in separatist violence this year. 近2,500人在今年的分裂主义暴乱中丧生。

In the weeks since flooding began, 16 people have died statewide. 洪水暴发几周以来，全州已有16人死亡。

▲He is an orphan — her parents are dead. 他是一个孤儿，父母双亡。

这个句子很明显是陈述一个事实，而不是强调“死亡”这个动作已经发生或刚刚发生，故不用 have died。