(1) Readers often associate Mark Twain with the Mississippi River. (2) Certainly, that river was important to his development as a writer. (3) He grew up along it, rafted on it as a boy, and became a
riverboat pilot on it as an adult. (1) No one can deny the river's importance. (5) The Mississippi, however
, was only one important place in Twain's development (6) At least as important were the
years he spent in the western territories. (7) After all, it was there that he first began using his pseudonym, Mark Twain.
Where should the paragraph be divided into two?
between Sentences 1 and 2
between Sentences 2 and 3
between Sentences 4 and 5
between Sentences 6 and 7