The demonstrations were provoked by the unexplained death of an opposition leader.

一位反对派领袖莫名身亡，引发了示威游行。

Soon after leaving Margate, for some unexplained reason, the train was brought to a standstill.

离开马盖特不久，不知什么原因，火车突然停了下来。

How such extensive damage could have been sustained so quickly remains unexplained.

如何这么快就造成这么大的破坏依然不得而知。