定语从句题目I know of a number of occasions --------people died from water pollution划线处填when,整句话怎么理解呢?

定语从句题目I know of a number of occasions --------people died from water pollution划线处填when,整句话怎么理解呢?
定语从句题目
I know of a number of occasions --------people died from water pollution
划线处填when,整句话怎么理解呢?

定语从句题目I know of a number of occasions --------people died from water pollution划线处填when,整句话怎么理解呢?
定语从句中,先行词应该可以在从句中充当一个成分.
先行词：Occasions
从句：______people died from water pollution.
把先行词放到从句中：People died from water pollution in the occasions.
翻译：我了解到很多次都有人都死于水污染.

引起人们大量死亡的起因是由于水体污染。
嘛，应该就是这样。

“我可以列举出大量水污染致死的事例”，这个是意译

我了解到人们大量死亡的原因是水污染。先行词为occasions 后面的从句不缺少成分所以用when