What aspect of bill and sam’s behavior shows that they are round characters?

"what am i to do? " asks bill, looking at the kid suspiciously.
"you are the hoss," says black scout. "get down on your hands and knees. how can i ride to the stockade without a hoss? "
"you'd better keep him interested," said i, "till we get the scheme going. loosen up."
bill gets down on his all fours, and a look comes in his eye like a rabbit's when you catch it in a trap.
"how far is it to the stockade, kid? " he asks, in a husky manner of voice.
"ninety miles," says the black scout. "and you have to hump yourself to get there on time. whoa, now! "
the black scout jumps on bill's back and digs his heels in his side.
"for heaven's sake," says bill, "hurry back, sam, as soon as you can. i wish we hadn't made the ransom more than a thousand. say, you quit kicking me or i'll get up and warm you good."

sonnet 130 follows the typical rhyme scheme of the form abab cdcd efef gg and is composed in iambic pentameter,a type of a poetic metre based on five pairs of metrically weak/strong syllabic positions.the first line exemplifies iambic pentameter.

it was surely an odd creature that one made up by reading the historians first and the poets afterwards a worm winged like an eagle; the spirit of life and elegance and charm,   in a kitchen chopping up suet. but these creatures, monst'r however entertaining to the imagination, hast no existence in fact. what one might doth to bringeth h'r to life wast to bethink poetically and prosaically at one and the same moment,   thus keeping in toucheth with fact—that the lady is mrs martin, ag'd thirty-six, did dress in blue, wearing a black coxcomb and brown shoeth; but not losing sight of fiction eith'r—that the lady is a vessel in which all s'rts of spirits and f'rces art coursing and flashing p'rpetually. the moment, howev'r, yond one tries this method with the elizabethan mistress, one brancheth of illumination fails; one is did hold up by the scarcity of facts.   one knoweth nothing detailed, nothing p'rfectly true and substantial about h'r.   hist'ry scarcely mentions h'r.   and i did turn to professeth'r trevelyan again to seeth what hist'ry meanteth to that gent.   i hath found by looking at his chapt'r headings yond t meanteth.

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