How can knowing the meaning of a prefix help us figure out the meaning of a new word?

Read this excerpt from "ain't i a woman? " by sojoumer truth in which three sentences does she make an emotional appeal to the audience by talking about her personal hardships? well, children, where there is so much racket there must be something out of kilter. {i think that 'twixt the negroes of the south and the women at the north, all talking about rights, the white men will be in a fix pretty soon.} but what's all this here talking about? {that man over there says that women need to be into carriages, and lifted over ditches, and to have the best place everywhere. nobody ever me into carriages, or over mud puddles, or gives me any best place} and ain't i a woman? look at me! look at my arm! {i have ploughed and planted, and gathered into bars, and no man could head me! } and ain't i a woman? i could work as much and eat as much as a man - when i could get it - and bear the lash as well! and ain't i a woman? {i have borne thirteen children, and seen most all sold off to slavery, and when i cried out with my mother's grief, none but jesus heard me! } and ain't i a woman? {then they talk about this thing in the head, what's this they call it? [member of audience whispers, "intellect") that's it, honey.} what's that got to do with women's rights or negroes' rights? if my cup won't hold but a pint, and yours holds a quart, wouldn't you be mean not to let me have my little half measure full?

Witch sentence contain an adverb clause

Read the excerpts from part 3 of "an occurrence at owl creek bridge." a rising sheet of water curved over him, fell down upon him, blinded him, strangled him! the cannon had taken a hand in the game. as he shook his head free from the commotion of the smitten water he heard the deflected shot humming through the air ahead, and in an instant it was cracking and smashing the branches in the forest beyond. *** a whiz and rattle of grapeshot among the branches high above his head roused him from his dream. the baffled cannoneer had fired him a random farewell. he sprang to his feet, rushed up the sloping bank, and plunged into the forest. *** as he is about to clasp her he feels a stunning blow upon the back of the neck; a blinding white light blazes all about him with a sound like the shock of a cannon—then all is darkness and silence! what function does the motif of the cannon serve throughout the story? the cannon continually pushes farquhar to continue his journey through his dream and back to reality. the cannon encourages farquhar to investigate whether his escape was a dream or reality. the cannon reminds farquhar that time is subjective and encourages him to move quickly in order to reach his home. the cannon represents farquhar’s romantic dream that he escaped his execution and will return home.