So much to learn

I feel like I've fallen so far behind in training Tango. Stupid, I know, since I've only had him for two months. But there it is. I see that he doesn't heel, he backs up to sit, he doesn't really know "down," he doesn't charge out of his crate when I tell him to, he comes only half the time when I call, and on and on. But then I remember that he tried to attack my sister and business partner (Hope) when he first came home and now she can do anything (practically) with him. He tried to bite our trainer (well, actually he did connect a little...) and now she can take his leash herself. He used to bark and lunge and snarl at people on the street, and now he just does that with other dogs. So yes, we do have a long way to go, but there's no time limit! And we've come a long way, so anything is possible.