syntax for text_field

Hi.... I have two tables named cis and software_cis which are polymorphically related. In the interface for editing the data in software_cis table, i specified the text_field component as     <label for="ci_name">Name</label>     <%= text_field 'ci.content', 'name' %>

But it printed an error: `@ci.content' is not allowed as an instance variable name

When i give <%= @ci.content.name%> the name field from software_cis table is printed. So please tell me the correct syntax of text_field. How can i refer the software_cis table using model ci?

Regards Suneeta