What are reasons why someone is considered a witch in Elizabeth George Speare's The Witch of Blackbird Pond?

In Elizabeth George Speare's The Witch of Blackbird Pond, any behavior that is contrary to the behavior of the rest of society serves as grounds for accusing someone of being a witch. Throughout the story, both Kit Tyler and Hannah Tupper are guilty of behaving in ways that are different from the ways of the Puritanical society around them.One way in which Kit acts contrary to the rest of society is by being able to swim. In the opening chapter, Kit asks for a spot on board the first longboat going to the Connecticut shore. The captain's wife, Mrs. Eaton, will be on board the boat, and Kit wants a chance to be with her up until the last minute and say goodbye. On the return trip to the ship, the Cruffs join as passengers. While on board the longboat, Goodwife Cruff's sorely neglected daughter, Prudence, accidentally drops her wooden doll into the water. When no one else will retrieve it for her, Kit jumps into the water herself and swims to retrieve it. Later, back on board the ship, Nat Eaton, the captain's son, informs her that Goodwife Cruff has been "insisting to [his] father that [Kit] is a witch," since Kit behaved disrespectfully by jumping into the water and swimming. Nat further explains to Kit the water trial for testing witches:

Don't you know about the water trial? ... . 'Tis a sure test. I've seen it myself. A true witch will always float. The innocent ones just sink like a stone. (Ch. 1)

Kit thinks the notion is ridiculous. Being from Barbados, her grandfather had taught her how to swim when she was still a very young child. Yet, despite the ridiculousness of the belief, Kit is beginning to be suspected of being a witch just because she is a girl who can swim.Later, in Chapter 9, Kit arouses suspicion of being a witch for teaching the children attending Mercy's dame school how to play-act. While teaching the children to read, Kit became inspired to make the lessons more interesting by having the children act out the Bible story they were reading. When the schoolmaster, Mr. Kimberly, and Reverend John Woodbridge pay an unexpected visit to Mercy's dame school, Kit is astonished to see how infuriated they  are by Kit's idea of "play-acting! And with the Bible" (Ch. 9). This is because play-acting is pretending a person is someone he/she is not, which is the same as lying and, therefore, sinful in the eyes of the Puritans. While the schoolmaster and reverend do not accuse Kit of being a witch at that point, her notion that play-acting is acceptable behavior certainly helps feed the colonists' suspicions about her.
Just as Kit is suspected of being a witch for being able to swim and for play-acting, Hannah is accused of being a witch simply because she is a Quaker, not a Puritan like everyone else in the colony. Since Quakers have different religious beliefs than Puritans, Quakers are considered sinful in the eyes of the Puritans.