translation.en: And basically, since we released it about three or four years ago, a lot of websites have started switching from the old CAPTCHA where people wasted their time to the new CAPTCHA where people are helping to digitize books.
translation.zh: 大约三四年前我们导入这个系统 许多网站已经从旧的验证码 换成新的来帮助书籍电子化 而不是浪费人们的时间