Betty: "You drank blood, Abby! You didn't tell him that!"
Abigail: "Betty, you never say that again! You will never--"
Betty: "You did, you did! You drank a charm to kill John Proctor's wife! You drank a charm to kill Goody Proctor!" (19).

I chose this quote because it shows how Abigail is definitely a witch. If you drink blood, you got some problems, and it witchcraft is easy to pin on her. Also, she wants to kill Goody Proctor since they had an affair. It is pretty obvious that Abigail will have more problems down the road. Even if she was not a witch, she was still involved in suspicious stuff and this is not the place to be involved in anything suspicious.

Let either of you breathe a word, or the edge of a word about the other things, and I will come to you in the black of some terrible night and I will bring a pointy reckoning that will shudder you (20)

I chose this quote because it is just more evidence that Abigail is a witch. No person would say something like this if they were not guilty and in big trouble, especially in a town full of churchies. The rules are too strict for any normal citizen to be willing to stick their neck out without risking suspicion by others.