Hey there! :D
An antecedent is something in a pre-existing/previous or late/past time frame. In latin, it means 'going before'.
For example,
Antecedents have led me to have to maintain a work out schedule.
(As in, past events or things that I have done previously to not be in shape, have caused me to want to workout and be in shape)
Think of the antecedent as a noun that replaces a proper noun.
It is a noun that refers to a proper noun.
'She' refers to the subject (proper noun) Rebecca, so 'she' is the antecedent.
I hope this helps!
~kaikers
