Expanding your vocabulary has never been so fun, or so easy!
Articulate! is a competitive, English-language game played by people all across the world.
You are presented with a word, and you must identify a synonym among 4 answer choices. You have 20 seconds to answer. When you do, you win points. The more points you win, the higher your world rank! Articulate! will also keep track of your streaks and points across sessions, allowing you to track your vocab-building progress.
There are thousands of words. Very helpful for SAT/GRE prep. Also just a fun way to learn new words with very little effort.
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NOTE: Many reviewers have noted that the app is broken, but this problem has been FIXED as of March 24, 2009. The fix does NOT require an upgrade.