some problems with "schemes of hyperbaton "

[The dreamer]

hi everybody
please help with this (i have an exam after tomorow)
in SCHEMES OF HYPERBATON
there are 3 types :
anastrophe
parenthesis
apposition

the problem is that i can't find the diffirence between parenthesis and apposition
for example

“Aunt Sarah who is really my mother's cousin will be visiting next week"
this is parenthesis

"Albert Einstein, perhaps the greatest of scientists, seemed not to have mastered the physics of hair combing"
this is apposition

but it seems to me the same
please help me

[The dreamer]

please help me
i need help......

[Tdol]

Sorry for not replying before, but I wasn't in the forum much yesterday. This is a bit of a killer question, but, I believe, when set off by commas, it is an appositive if it is a a noun phrase. If the second said 'who was perhaps...' then it would no longer be an appositive.

[The dreamer]

thank you