Why do you use commas

Ead this excerpt from the introduction to wheels of change by sue macy. imagine a population imprisoned by their very clothing; the stiff corsets, heavy skirts, and voluminous petticoats that made it difficult to take a deep breath, let alone exercise. add to that the laws and social conventions that cemented a man's place as head of the household and holder of the purse strings. how suffocated women must have felt. and how liberated they must have been as they pedaled their wheels toward new horizons. why does the author include this excerpt?

Read the excerpt from the time traveler's guide to elizabethan england. simon forman, who does attend plague sufferers, is a rare exception: this is because he has himself survived the disease and believes he cannot catch it again. however, his remedy amounts to little more than avoiding eating onions and keeping warm. he has a recipe for getting rid of the plague sores that will afflict you afterward if you survive the disease; but that is a very big "if.” it seems the best advice is provided by nicholas bownd in his book medicines for the plague: "in these dangerous times god must be our only defense.”which lines best summarize the excerpt?

How does hosseini use details of exposition to link amir’s life in afghanistan with his life in the united states?