How to set a fixed width for the resizeable element

I'm working with the resizable div tag. I have created a text box and
appended it to the resizable div tag so that I get a resizable text
box.
My problem is once I create and resize a text box,the next textbox is
created to the previous resized text box. I want it to be of the
default size. How do it do that? Where Should I set the default size?