谁知道英文怎么写

I hope you're the only one who knows it.

但愿只有你知道这件事。

Who knows most says least.

懂得最多的人，说得最少。

Who knows what they look like?

谁知道他们长什么样子呢？

Who knows when we'll be done?

谁知道我们什么时候完成呢？