It's a little frustrating in that there is a 5-minute time limit and if your answer isn't correct you have to erase it before entering the next guess. Also, your correct answers are displayed in order of their frequency of use, not alphabetically, so you can't instantly see if you've already tried something.
As much as I read, I really expected to do well, but only got 31/100 my first try. My excuse, the tv is on and kids are getting ready for bed and husband is talking to his mother, in other words, life!
Go here and try.