1-4 look correct to me.
for #5, you are correct that to come is not a prepositional phrase because there is no object. If I were you, I'd leave it alone and keep the one next it. all others look correct.
Communication can change us in different ways. So it depends on what you're talking about.
Assuming the underlined word is "leader," the correct answer is predicate nominative. Predicate nominative refers to a word that is in the nominative case and completes a copulative verb. In this sentence, the word "leader." Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help.
