Symfony 2在用户站点上动态添加字段以形成

I am working on survey bundle. The goal is to provide user a fully working survey system. I have already prepared a backend which allows you to create survey, add questions (open text, radio buttons, checkboxes), make questions required or not, activate survey, generate tokens and send link to the survey with token on email. Of course i also have frontend which shows survey and saves answers. Now i want to add another possibility. A question with answers (radio or checkbox) and comment. For example:I am working on survey bundle. The goal is to p