Thanks for the tip, Brenda. Actually she does walk very well. I use a harness on her too. Not that particular one, however. My problem is that when we see another dog being walked she becomes very aggressive toward that dog. I have to remove her from the area. The training now is to stop the aggression and make her obey me when I tell her to "leave it". She's good with sitting but not when she gets to the aggression peak. It's exhausting.
So, now she is doing very well with the training and obeying me. Two little boys rode past us on their bikes and she was calm.