When the suddenly rain fell, I was in a open place, where I had no place to hide.

突然下雨的时候，我在一个空旷的地方，我找不到地方躲雨。

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Suddenly, I noted that the rain had stopped.

突然，我注意到雨已经停了。

《柯林斯英汉双解大词典》

The sky suddenly went dark and it started to rain.

天空骤然转暗，随即下起雨来。

《牛津词典》

Suddenly the rain came.

BBC: Picture power: Collapsed bridge

You know, these people thought the worst was over and suddenly to see those skies darkening again and for that rain to come back again and the winds to pick up again, it's going to terrify them I'd imagine.

NPR: Myanmar Still Barring Relief, Reporters

But he also received perhaps the biggest break of the tournament when his shot into the par-5 13th spun back off the green and was headed down the slope into the tributary of Rae's Creek when it suddenly stopped, a blessing from a day spent in the rain.

NPR: Scott Beats Cabrera In A Playoff At Augusta