"She found her cabin still dry, but as she rummaged about, she heard a key turn and suddenly realized the steward was locking the stateroom door to prevent looting."
The main thing in this excerpt is "to prevent looting."
The term or overall feeling of the piece is called the theme of the story.
Answer:
A noun phrase, or nominal, is a phrase that has a noun as its head or performs the same grammatical function as a noun. Noun phrases are very common cross-linguistically, and they may be the most frequently occurring phrase type
Example:
Examples of noun phrase as direct object: I want a skate board. Should we buy the yellow house? Examples of noun phrase as object of preposition: Jeff rode on a skate board. Karen lives in the yellow house.