Add more elements to a HTML-form that is posted to a php-script
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I am working on a script where the user can write information in a HTML-form that will be downloadable in a pdf-file.

Some of the users might want to add more information than others (e.g. several names), because of this I want to add the functionality to add more textboxes that will send the information to the PHP script.
![enter image description here][1]


  [1]: http://i.stack.imgur.com/pvisW.png

What is the best method of doing this?