In grammar rules, an antecedent can be identified in a sentence because it is later replaced by a pronoun. An antecedent also refers in a sentence to something that happened in the past.
In the sentence provided as an example, the Venetian 'merchants' is the noun that is later replaced by its respective pronoun (theirs). The verb brought also tells us it was something that happened in the past.
A writer would think about what emotions they would portray in the poem. They would also consider what effect it would have on people and how it may change the way someone thinks.
Hamlet killed Polonius on accident, realizing that someone was listening to his conversation with his mother in a deranged state. This proves Hamlet to be "crazy", and turns Hamlet into a more disliked person among the kingdom.
