When Professor Dumbledore invited me to Hogwarts I was excited to feel the familiar bumpy ride of the carriage taking me to the front steps, the towers, the squid, the trees, and the corridors which echoed my steps.
Luckily enough, I have another question that can apply to the same sentence. I read a post in this community a while back about when it is appropriate to use "which" and when it is appropriate to use "that". I agree that if I were saying "The corridors, which echoed my steps, were quite spacious," then I would use a comma before "which." But what about the last part of the sentence above--is a comma before "which" required, or should I simply use "that," or is some other element needed?
I do hope this is clear! Thank you in advance.