I posted a thread about Recaptcha.
A quick search on Wiki shows that you only have to get 1 word right. HOWEVER, there are actually a lot of lenient scoring criteria they use...
For example, for a word like collar, it's pretty obvious it's Ls, and I put Is instead. In fact I misspelled both words using Ls and recaptcha took my responses. I tried many times, and if you're really close, it will let you go. I've only failed recaptcha ONCE in my life and it was while I was experimenting with it. I don't remember too well but it doesn't seem like there's a predetermined CORRECT word and a wrong word. Both are words for you to solve. But i believe that may be because the leniency they give me allows me to fail both anyway...
The other CAPTCHAs are complete fail. Some just piss me off and I refresh like 10 times. It's retarded. It's not even like I have a miscalibrated monitor either to have poor gamma/contrast. ReCaptcha should be the STANDARD.
CORRECTION: There is a preset word you ahve to get right. I typed qweuiryakdfjhgadsf + correct word and about half the time it passes me meaning that half the time it's the 2nd word that you have to get correct. You just have to get CLOSE..... You can swap ds for bs and Ls for Is and throw in 0s instead of Os.... yeah you get it.