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Our advertising partner is Google and they automatically pair up ads on Quizlet with their 3rd party advertisers; we don’t work directly with advertisers. This works very well the majority of the time, but sometimes clearly undesirable advertisements come through. We do our best to remove these as soon as we see them or they are reported by users.
If you spot anything you think is inappropriate, or encounter any other problems, please note the URL that the ad leads to and let us know immediately.
Also, if you want to get rid of ads on Quizlet completely (surf Quizlet ad-free), you can do so by donating $10 to Quizlet using this page: http://quizlet.com/donate (note that you must be logged in to Quizlet at the time you donate for this to work).