the parameter is nil ?

Hi,
   I use scaffold to create the task model controller and view, it
contains action as "show", "new", "create", etc.
   Then, I give an "id" parameters to the view - new.rhtml, so the URL
could be like "http://localhost:3000/tasks/new/1" , and I wish when I
click the create button in "new.rhtml", the following "create" action
could get this id parameter, so I coded like this: