How do I use the tiles at the top and bottom that aren't connected in level 18 of alphabetty

Chee_Chee

In the game alphabetty, level 18, how do I use the disconnected letters at the top and bottom?

StuckInATree

When you make 4 letter words you will be rewarded with a little crown on a tile, when you use this crowned tile when making a word, it will activate and pop one of those bubbles, that's how you pop them! FYI crowned tiles will always help with the objective of the level so they come in pretty handy!