In The Crucible, in what ways has Mary Warren changed, and what changed her?

In
outward terms, Mary Warren changes from a rather timid young girl into a much more confident,
assertive character. This is because, for the first time in her life, she's now the center of
attention. Adult authority figures in court hang on her every word, and this gives her a sense
of power and control. It also gives her the confidence to resist John Proctor's impassioned
pleas to tell the truth instead of blindly following Abigail Williams.

At
heart, though, Mary doesn't change all that much. Her newfound assertiveness is entirely
artificial, created by the strange circumstances of the Salem witch craze. Deep down, she
remains nothing more than a frightened child, unable to stand up for what's right for fear of
what the wicked Abigail might do to her.