You never know what you can do till you try можете изменить это предложение в вопросы (disjunctive,alternative,to the subject,special,

You never know what you can do till you try
Do you know what you can do before (till)you try? (General)
Do you know what you can do or make before(till) you try?(Alternative)
You never know what you can do till you try, do you?(Disjunctive)
Who never knows what you can do till you try?(To the Subject)
What don't you know till you try?(Special)

You never know what you can do till you try, do you? Do you know what you can do till you try ? Do you know or think what you can do till you try? Who never knows what you can do till you try ? What don't you know till you try ?