In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: Music, like literature, is an art that deals with sound.
P: Literature makes use of words which are sounds.
Q: They also have meanings.
R: And the writer must be concerned with the effect produced by the sounds he uses.
S: But words are not only sounds.
S6: They refer to specific things other than themselves such as objects an ideas.
The Proper sequence should be: