Adobe Illustrator: 500pts: Problems using caligraphic brushes, please help

Hi there,

Can anybody help? I am trying to produce some simple brush effects in Adobe illustrator CS. It is quite difficult to explain exactly in words so I have attached this file which outlines the exact effects I am trying to achieve, I think they are pretty standard effects but its thrown me and i am confused :-)  http://www.easyasabc.com/trying_to_acheive.jpg  (very small in file size)

On the picture example above, you will notice that the brushes start at a thin point, generally get larger and return to thin point. As i say the picture is self explanatary.

I have tried many times to produce similar effects but can never get what I want it to do, again.. difficult to explain in words but this attached file shows you what I get http://www.easyasabc.com/what_i_get.jpg   (very small in file size)

Basically I can get it to start at a thin point but generally it grows larger and stops at the end and doesn't return back to a thin position. I think the picutre above shows this.

I hope somebody can help, I presume i am doing it correctly with the caligrafic brushes. I basically draw a line with the pen tool and apply a brush, of course I know you can change these settings which i have tried but can't seem to get the desired effects.

I hope somebody can help with my situation, its so hard to describe the problem thats why i have included the links of the jpg's pic files to illustrate what i am doing and getting.

Thank you i advance for any suggestions or help

Ian