How is your English? The Google wants you to be perfectly understood that language, then created a game on the web that makes you spell and pronounce the words according to their level of knowledge.
The game calls Spell Up and is one of the experiments Chrome, like that of play Lego or that transforms 3D gaming sites. It was created in partnership with game designers and teachers using the voice recognition API on the web and to play you must have a basic knowledge of English.
The goal is to build a tower with words, initially only spelling (so you need to know how to say the letters and understand the word that Google will tell you) and then also answer each one correctly. When you miss the story fall apart and you have to start again the level.
Spell Up is fun, but voice recognition is not perfect, so it may occur to understand something different from what you said and unjustly need to start again. But for those for some time without speaking English, play to give that desenferrujada.
It is recommended to play in Chrome, both the computer and on tablets and smartphones Android; on iPhones and iPads, Google warns, you need to type instead of talk.