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: The dictionary is the best friend of you task.
P : That may not be possible always.
Q : It is wise to look it up immediately.
R : Then it must be firmly written on the memory and traced at the first opportunity.
S : Never allow a strange word to pass unchallenged.
S6: soon you will realize that this is an exciting task.
The Proper sequence should be: