Read the paragraph, which is a summary of a slave narrative by Olaudah Equiano. [1] While he was working for Thomas Farmer, he began to buy fruits and other goods and sell them himself. [2] He faced insults and difficulties doing this; however, he was determined to continue making money, which he did. [3] He wanted to obtain enough savings to buy his freedom, which Robert King had promised him he could do for the same amount that King had paid for him. [4] When he had saved enough money, he bought his freedom from King and lived the rest of his life as a free man.

Which sentence in the paragraph is structured differently than the others?