Which of the following singular nouns changes vowled when made plural

What is the primary purpose of this blog? to inform people about the new sports park to entertain people with details about the warbler to persuade people to protect the warbler to convince people to support the city council

Ineed writing a reflective essay about hiking?

Explain the effect of the rhetorical questins for the below paragraph."i pinched myself: was i still alive? was i awake? how was it possible that men, women, and children were beiing burned and that the world kept silent? no. all this could not be real. a nightmare soon i would wake up with a start, my heart pounding, and find that i waas back in the room of my childhood, with my "