What was odd about the night? why was the moon sulking lesson the walrus and the carpenter

the answer is nurse.

often a noun phrase is just a noun or a pronoun:

people like to have money.

i am tired.

it is getting late.

the pronoun reference replaces a noun, but you have to make sure there's no room for confusion.

in the first sentence "her" could be referring to shely or to the sister. the answer there is "shelly called her sister and told her about the new baby."

in the second sentence "it" could be referring to the roof or the floor. the answer there is "since the roof leaks on the family room floor, we need to repair the roof."