Ruby on Rails：同一表单中的多个输入字段 - 更改ID /值

Have a page where there are multiple input fields of the same thing, Posts. Right now, when a user enters in a question for, let's say 3 fields, the only one that saves to the database is the last one. Whereas, it should save all three and give them each it's own post_id. Also; if the user doesn't enter anything in for the other fields, it should not save in the database either.Have a page where there are multiple input fiel