Pre- (before)
Pre-
Before; earlier.
Vikram preheated the oven before baking the cake.
Preview
A look at something before others see it.
The class watched a preview of the school play.
Prepaid
Paid for in advance.
Joseph topped up his prepaid phone card at the shop.
Remember: Pre- = before; think of a pre-match warm-up. Don't mix it up with pro- (forward, for): proceed, protect.