Just like PvZ with adventure mode, survival mode and more, PvZ adventures game has a few modes as well. The main mode that you are playing with is Road Trip with various stages for you to pass. Some stages are easy and some are difficult to pass. Town building mode is used to prepare and ready plants and currencies for the fight. Brain ball is still under development and will be released soon for more human interaction. Battle between actual FB users is involved and it is anticipated to make the game more exciting.
Plants vs Zombies Adventures game modes
For more about individual modes, see Plants vs Zombies Adventures game modes below:
For a complete guide on PvZ Adventures Beta, go here.