In the question below, each passage consists of six sentences. The first (S1) and sixth (S6) sentences are fixed. The middle four sentences P, Q, R, S are jumbled. Find the proper order of the four sentences.
S1: The library is a place where knowledge is preserved and shared with all.
P: Students and researchers often visit to find useful information for their studies.
Q: It houses thousands of books, journals, and digital resources on various subjects.
R: The peaceful environment helps visitors focus and absorb knowledge effectively.
S: Librarians play a crucial role in organizing and maintaining these resources.
S6: Thus, the library serves as a treasure trove of wisdom for generations.