I do not even know what the story is so no one is going to be able to answer that question.
Answer:
The question wants you to add more information to the sentence you provided by doing what?
So she can get what she wants to say off her chest without allowing her mother to know that she loves Romeo
I can't type you a whole essay but i can give tips for each paragraph so you know what to write about.
P1: introduce topic - tsunami
P2: describe how it starts
P3: describe how it ends
P4: describe after effect
P5: conclude with interesting fact