Curves look segmented and are separated from the polyline

[aysun23570183w6yy]

Hi everyone. Curves in pdf or eps files exported from Autocad look segmented and separated from the actual line. I will be grateful for any help. 

[Met1]

Are you saying they only look like that when opened in Illustrator, i.e. pdf looks fine in Acrobat?

Take a screenshot of it in Autocad for us to compare what it should look like...