在你尝试之前你永远不会知道 用英文翻译

You never know before trying.

you will never know unless you try.

You have to try it in case you never understand it.
You will never know unless you have given it a shot.
You must try it to know, otherwise you will/can never understand it.
You can never know it before give it a try.
Give it a go, otherwise you will never know.
仅供参考，欢迎指正