If we changed the word antidote to gift, what effect would it have on the meaning of the
sentence?

if you changed antidote to a gift then it would have in impact as if  for example this sentence:

Antidote

"He gave Lucy the antidote of the poison, and as she poured it over her brother, he returned to his normal state, only, he had forgotten his memories"

Gift

"He gave Lucy the gift the of the poison, and as she poured over her brother, he returned to his normal state, only, he had forgotten his memories"

Oof I don't know if this would explain a lot, just say it has completely different meanings in a sentence depending on what it means.

sorry bro oof

the conservative movement opposed the women´s suffrage like josephine jewell dodge comanding the national association opposed to woman suffrage.