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: He could not rise.
P: All at once, in the distance, he heard an elephant trumpet.
Q: He tried again with all his might, but to no use.
R: The next moment he was on his feet.
S: He stepped into the river.
S6: It was colder than usual.
The Proper sequence should be: