最快的流水用什么成语来形容呢英语

To describe the fastest flowing water in English, the most suitable idiom would be:

"Like a mountain torrent"

或更常见的表达：

"Swift as a rushing river"

若强调不可阻挡的迅猛之势，可用：

"To flow at breakneck speed"（虽非传统成语，但生动贴切）

具体解析：

1. "Like a raging torrent"

"The river surged forward like a raging torrent."

2. "Swift as a mountain stream"

3. 非成语但地道的表达：

示例：

根据上下文选择最贴切的表达即可！