Answer:
The Swallow was a bird but he was very obedient. Whenever the Happy Prince requested the swallow to help the people who were in miserable condition, he obeyed the prince's order.
the second one because a comma shouldnt be used after the word and but it is needed while listing things
The first one bc it doenst have like or as and its comparing teo things and the others are either similies or personification
Because you want elaborate your topics with a great word choice to capture the readers attention
I guess the answer is 2 and 4... I hope it help ..